Shared Flashcard Set

Details

Biological Concepts of Health: Midterm
University of Guelph BIOL*1080
616
Biology
Undergraduate 1
02/09/2015

Additional Biology Flashcards

 


 

Cards

Term
23 and Me
Definition
A company that, for $100, will analyse your DNA to calculate your personal risk for various diseases.
Term
Abdominal cavity
Definition
A division of the ventral body cavity. Contains the digestive system, urinary system, and reproductive system.
Term
Accidents
Definition

A leading cause of death in Canada.

4.1% of deaths.

Term
Acetylcholine
Definition
A neurotransmitter that is released by neurons at the junction between neuron and skeletal muscle, causing contraction. Does not fall into any of the chemical classifications of chemical messengers. Has the opposite effect of norepinephrine. Controls arousal, sleeping/waking, learning, memory, and sensory information.
Term
Acne
Definition
Caused when a hair follicle or oil gland duct is blocked by dead skin cells. The blocked duct fills with sebum. More common in adolescence when oil glands are larger and produce more sebum. Occurs mainly in areas high in oil glands such as the face, chest, upper back, and shoulders. Includes blackheads and whiteheads. Red swelling is caused by swelling of surrounding blood vessels. If an acne spot becomes infected by bacteria it becomes a pustule. Acne is treated with topical or oral medications.
Term
Acquired brain injury (ABI)
Definition
Brain injury caused by disruption in the oxygen flow. Includes strokes, aneurysms, heart attacs, brain tumors, anoxia, meningitis, seizure disorders, and substance abuse.
Term
Actin
Definition
A protein found in strations of muscle cells. Interacts with myosin to make muscle contractions.
Term
Action potential
Definition
A sudden change in the difference of charge between the inside and outside of an axon when an impulse is sent down the axon. First there is depolarization, then repolarization.
Term
Adaptation and repair system
Definition
Part of the local support and defence system.
Term
Adaptive traits
Definition
Traits that allow an organism to thrive in its environment. Develop through natural selection.
Term
Addiction
Definition
After long-term overexposre of the brain to a substance, more is needed to experience the same effect because cells down-regulate.
Term
Adenylate cyclase
Definition
Catalyzes the conversion of ATP to cAMP.
Term
Adhesion junction
Definition

aka Desmosomes

Cell junctions that are less rigid than tight junctions. The plasma membranes of the two cells are not touching, but held together with intercellular filaments that attach to a thicker area of the membrane. The cells may slide slightly against each other. Found in cells that must stretch, such as skin, cervix, and cardiac muscle.

Term
Adipose tissue
Definition

aka Fat tissue

A type of loose connective tissue proper Found under the skin and around the kidney and heart. Stored energy, and insulates and cushions orans. A shock absorber. Contains cells specialzed for fat storage. Long-term energy storage.

Term
Adolescence
Definition
A socially and culturally created concept only a few generations old. Many societies do not recognise adolescence.
Term
Adrenergic receptor
Definition
A receptor that binds to epinephrine and norepinephrine. Includes α1 and α2, which have high affinity to norepinephrine, β2 which has a high affinity to epinephrine, and β1 and β3 which have equal affinity to both epinephrine and norepinephrine.
Term
Adulthood
Definition
Divided into three stages: early adulthood middle age, and the elderly. Adults are less likely to engage in risk-taking behaviours and more likely to engage in healthe behaviour.
Term
Aetiology
Definition
The cause of a disease.
Term
Affinity
Definition
The strength of the bond between a receptor and a ligand.
Term
Aging
Definition
Caused when the CCN's function is reduced over time. Decreased memory, decreased touch sensitivity, diminished wound healing capacity, diminished reproductive capacity, motor loss, physical impairnment, chronic conditions, poor health, poor digestion. Not necessarily a negative experience. Poses challenges, but is not in itself a problem.
Term
Agonist
Definition
A ligand that binds to a receptor and triggers a response. May have to compete with antagonists.
Term
Albinism
Definition
An inherited condition where melanocytes are incapable of producing melanin. Occurs in one out of every 10,000 people. Not specific to race. Albinos lack pigment in the eyes, hair, and skin. Eyes and skin are pinkish in colour.
Term
Albumin
Definition
A carrier protein that carries a wide range of lipophilic hormones.
Term
Alzheimer's disease
Definition

Areas of the brain that function in the hippocampus and cerebral cortex, which function in memory and intellectual functioning, lose large numbers of neurons and astrocytes. Acetylco Loss of memory, especially of recent events. Personality can change.

Ronald Reagan had Alzheimer's disease.

Term
Amines
Definition
A chemical classification of chemical messengers. Derived from amino acids. Have an amie group, NH2. Most are lipophilic. Includes catecholamines, serotonin, and thyroid hormones. All, except thyroid hormones, are derived from amino acids.
Term
Amino acids
Definition
A chemical classification of chemical messengers. Lipophilic. Includes glutamate, aspartate, and GABA. Obtained from the diet. Neurotransmitter amino acids are synthesized in the cytosol of the presynaptic neuron.
Term
Amplifier enzyme
Definition
An enzyme that catalyzes the production of second messengers.
Term
Amygdala
Definition
Part of the limbic system. Gives us long-term memory. Has connections too sensory areas and emotion centres. Links memories to emotional states. Active when sleep-deprived.
Term
Amyotrophic lateral sclerosis (ALS)
Definition

aka Lou Gehrig's disease

Motor neurons in the brain and spinal cord die and stop sending messages to skeletal muscles. The person loses control of their body and dies from respiratory failure. Sensory neurons are unaffected, so the person has full awareness the whole time.

Term
Androcentricity
Definition
Viewing the world from a male perspective. Could result in overgeneralization of study results.
Term
Animal research
Definition
Tests done on live animal subjects. Common test subjects include C. elegans, Drosophilia melanogaster, rats, mice, miniature, swine, and primates.
Term
Animals
Definition
A kingdom of Eukarya.
Term
Antagonist
Definition
A ligand that binds to a receptor and does not trigger a response. May compete with agonists, decreasing the magnitude of response.  Many drugs are antagonists.
Term
Anthropocentrism
Definition
A human-focused perspective in biology.
Term
Arachidonic acid
Definition
A phospholipid. Release from the membrane is catalyzed by phospholipase A2. Enters the cyclooxygenase or lipoxygenase pathway.
Term
Arachnoid
Definition
A spider web-like layer between the dura mater and pia mater mininges that attaches the two.
Term
Archaea
Definition
A domain of life. Prokaryotic.
Term
Areolar tissue
Definition
A type of loose connective tissue proper. Widely distributed. Found under the skin, between muscles, surrounding glands, and wrapping small blood vessels and nerves. Wraps and cushions organs. A universal packing material. Embedded in a gelatinous matrix which is easily shaped. Permits muscles to move freely over each other. Anchors the skin to underlying tissues and organs.
Term
Arrector pili
Definition
Muscles that surround hair follicles. When temperatures are too high, they relax, keeping the damp, cooling hairs close to the skin. When temperatures are too low, they contract, causing piloerection.
Term
Ascending tracts
Definition
Clusters of myelinated axons in the white matter of the spinal cord. Bring information from the body to the brain.
Term
Aspartate
Definition
An amino acid chemical messenger that is derived from adding an amine group to certain Krebs cycle intermediates.
Term
Association functional areas
Definition
Areas of the cerebrum that analyze and act on sensory inputs. Integrate information from sensory areas with information from memory areas to recognize what sensory areas are sensing. Includes the prefrontal cortex.
Term
Astrocyte
Definition
Cells in the nervous system. Form a astrocyte cloud network in the brain. Provide neurons with nutrients. The connectors of all parts of the brain. Co-ordinate function of the vetricles, and at the nodes of Ranvier. Super-hubs for neural networking. Have calcium waves signalling. Have astrocyte feet that are part of the blood-brain barrier.
Term
Astrocyte foot
Definition
Extensions of astrocytes that are part of the blood-brain barrier. Attach to the pericyte surrounding blood capillaries. Have tight junctions.
Term
Autocrine
Definition
A class of peracrines. Act on the same cell which secreted them. Often an autocrine regulates its own secretion.
Term
Autonomic nervous system
Definition
Part of the peripheral nervous system. Results in involuntary, subconscious activities that keep the body functioning properly. Includes the sympathetic nervous system and parasympathetic nervous system.
Term
Axon
Definition
Part of a neuron. A (usually singular), long extension that conducts outgoing impulses away to other neurons. May be myelinated. Secretes neurotransmitters. Can be up to a meter long!
Term
Baboons
Definition
A primate that is researched in the wild.
Term
Bacteria
Definition
A domain of life. Prokaryotic.
Term
Basal cell carcinoma
Definition
A type of skin cancer. The most common type of skin cancer. Found in the deepest layer of the epidermis
Term
Basement membrane
Definition
The surface of epithelial tissue which binds to the unerlying connective tissue.
Term
Biocentrism
Definition
A non-human-focused perspective in biology.
Term
Biology
Definition
The study of life. An understanding of biological systems requiring both reductionist and holistic thinking. Perspectives in biology include anthropocentrism, biocentrism, reductionism, and holsim. Defining ideas of biology are cells, genes, evolution, chemistry, and logic units and information flow in biological systems.
Term
Biomarker
Definition
Measurable factors that can be used as early warning signs for diseases. Separates symptoms of diseases from normal aging process. Has normal ranges; if the patient exceeds the range, further investigation is prescribed. Must be routinely monitored over time with each individual. Example: height, endurance, strength.
Term
Biomedical model
Definition
Symptoms are able to be cured through medical intervention. Assumes direct causal relationship between illness, symptoms, and underlying pathology. Reductionist; allows little room for subjectivity. Fails to account for people responding to treatments differently than others.
Term
Biophilia
Definition
The instinctive bond between people and the environment.
Term
Biopsychosocial model
Definition
The model that is widely accepted today. Illnesses have physical underlying causes, but are also affected by individual responses. The mind plays a role in the manifestation and response to illnesses. There is subjectivity from beliefs, expectations, emotions, and culture.
Term
Biosphere
Definition
The part of the earth that supports life. Extends 11 km above sea level and 11 km below.
Term
Black bile
Definition
One of the four humours in the humoral theory. Associated with autumn and the cold and dry. Associated with a melancholic, sad temperament. It ws thought that melancholic women were more likely to get breast cancer.
Term
Blackheads
Definition
A type of acne. Caused when the sebum blocking the pore is mixed with melanin, causing a dark spot. It is not dirt as some people think.
Term
Blood
Definition
A type of specialized connective tissue. A fluid found in blood vessels. Transports oxygen, carbon dioxide, nutrients, hormones, wastes, and fights infections. Cells are called formed elements. Matrix is called plasma. Protein fibres are soluble proteins visible when blood clots.
Term
Blood (humoral theory)
Definition
One of the four humours in the humoral theory. Associated with the spring, and the hot an wet. Associated with a sanguine, optimistic personality.
Term
Blood-brain barrier
Definition
Mechanisms that select substances permitted into the cerebrospinal fluid from the blood. Tight junctions between cells of the capillary walls. Filters what can pass into the brain. Lipophilic molecules can pass through faster. Must bass through the endothelial cell, the pericyte, and astrocyte foot.
Term
Body cavity
Definition
Protective cavities in the body in which organs are suspended. Protected from being damaged when we move around, and allows organs to slide past one another and change shape. There are two main body cavities: ventral and dorsal.
Term
Body temperature
Definition
Set point is at 37 ºC, but differs from person to person. A negative feedback system controlled by the hypothalamus in the brain. If temperatures are too high, sweat glands increase sweat secretion, blood vessels dilate, the arrector pili muscles relax, and the person may seek shade and/or remove layers of clothing. If temperatures are too low, sweat glands reduce sweat secretion, blood vessels contract, arrector pili muscles contract causing piloerection, metabolic activity increases, and the person may shiver and cross arms to generate and conserve heat.
Term
Bone
Definition
A type of spexialzed connective tissue. Provides support and protection, storage of lipids (yellow marrow), calcium, and phosphorus, produces red blood celsl (red marrow0, and serves as a lever for muslce to act on. Actively metabolising. Has blood supply, allowing for quick healing. Matrix is hardened with hydroxyapatite and collagen fibres, making bone rigid and strong. Calcium is stored here but is also needed for bon strength; acts as a buffer for blood calcium levels.
Term
Botox
Definition
A populat treatment for wrinkles. A toxin from the bacteria that cause botulism. Injected into facial muscles, temporarily paralyzing them. The muscle contractions that form wrinkles are no longer possible, and the skin smoothes out. When ability to contract muscles returns the treatment must be repeated.
Term
Brain
Definition
A part of the central nervous system. Found in the cranial cavity. Gives us emotions, personality, memories, and is the control centre of many feedback loops for homeostasis. Weighs less than 3 pounds. Parts are the cerebrum, corpus callosum, thalamus, hypothalamus, cerebellum, brainstem, hippocampus, amygdala, and olfactory bulb.
Term
Brain injury
Definition
Common, but have no visible symptoms. The "silent epidemic". Includes acquired and traumatic brain injuries.
Term
Brainstem
Definition
A part of the brain. Includes the medulla oblongata, midbrain, and pons.
Term
Burns
Definition
Classified by how deep into the skin they go. Includes first, second, and third degree burns.
Term
C. elegans
Definition
A test animal. A nematode. We have the genome of this animal sequenced. Individuals are either male or hermaphrodites. Periodically they enter sleep-like states.
Term
Caffiene
Definition
A naturally occuring physiological agonist. Lipophilic, so it can pass through the blood-brain barrier quickly.
Term
Calcium
Definition
Stored in the bones and proides bone density. Calcium levels in the blood are maintained within a narrow level by homeostasis. Calcium is moved during pregnancy and lactation. A good first messenger because it is in higher concentrations in the extracellular fluid than in the cytosol.
Term
Calmodulin
Definition
A receptor for calcium that releases second messenger. Activates protein kinases for the phosphorylation of proteins.
Term
cAMP phosphodiesterase
Definition
An enzyme which deactivates cAMP.
Term
Canadian Council for Animal Care
Definition
An organization that monitors the ethics in animal testing research.
Term
Canadian Institute of Health Research (CIHR)
Definition
A Canadian government funding source for medical research.
Term
Cardiac muscle
Definition
A type of muscle. Found in the walls of the heart. Pumps blood through the body. Branched striated cells with one nucleus each. The plasma membrane is strengthened by special junctions promoting rapid conduction of impulses through the heart. Has involuntary contraction.
Term
Cardiovascular system
Definition
Transports nutrients, respiratory gases, hormones, wastes, heat, immune cells and antibodies. Regulates pH.
Term
Carrier protein
Definition
A protein that binds to lipophilic hormones such as steroids and thyroid hormones, allowing them to dissolve into the bloodstream. Includes corticosteroid-bindgin globulin and albumin. An equilibrium is established between hormone bound to carrier proteins and free hormone.
Term
Cartilage
Definition
A type of specialized connective tissue. A tough but flexible semisolid found in the nose, rings of respiratory air tubules, external ear, and in certain joints of the skeleton. Provides flexible support, cushioning, protection, and serves as a lever for muscles to act on. Cells are chondrocytes. Matrix is called lacunae. Lacks blood vessels and nerves. Slow repair. Includes hyaline cartilage, elastic cartilage, and fibrocartilage.
Term
Catechol group
Definition
A six carbon ring. Found in catecholamine.
Term
Catecholamine
Definition
A category of amine chemical messengers. Have a catechol group. Derived from tyrosine. Includes dopamine, norepinephrine, and epinephrine.
Term
Cell
Definition
The smalles unit of life. Composed of molecules. Some organisms are a singular cell, others are composed of trillions of cells together. Cells can divide, forming new cells, enabling reproduction, growth, and repair. All cells are formed from pre-existing cells. Cells form tissues.
Term
Cell body
Definition
A part of a neuron. Houses the nucleus and most organelles.
Term
Cell junction
Definition
Attachments that form between the cells. Include tight junctions, adhesion junctions, and gap junctions.
Term
Central canal
Definition
In the spinal cord. Cerebrospinal fluid circulates through it.
Term
Central nervous system (CNS)
Definition
Part of the nervous system. Includes the brain and spinal cord. The peripheral nervous system branches off of it. Neurons cannot repair themselves or reproduce. Protected by the skull, vertebral column, meninges, and cerebrospinal fluid.
Term
Cerebellum
Definition
A part of the brain. The "auto-pilot" of the brain. Co-ordinates sensory-motor voluntary movement. Stores memory of learned motor patterns such as walking and poture. Information about joint positioning and tensions in muscles and tendons.
Term
Cerebral cortex
Definition

aka Gray matter

Billions of neuroglial cells, interneurons, cell bodies, and unmyelinated axons. In the cerebrum. 2.5 mm thick, but highly folded with large surface area. Integrates information. On top of white matter.

Term
Cerebrospinal fluid
Definition
Fluid that fills the spaces between meninges, ventricles, and the central canal. Formed in ventricles by ependymal cells. Circulates through the central canal and is absorbed into the blood. Provides shock absorption, support nourishment, and waste removal to the centtral nervous system.
Term
Cerebrovascular diseases
Definition

A leading cause of death in Canada.

6.1% of deaths.

Term
Cerebrum
Definition
A part of the brain. The most prominent part of the brain. 83% of the brain's weight. Contains sensory, motor, nd association areas. Has two hemispheres which are separated by the longitudinal fissure, and connected by the corpus callosum. Each hemisphere has four lobes: frontal, parietal, temporal, and occipital.
Term
Channel-linked receptors
Definition
Ligand-gated channels that bind to lipophobic messengers. Include fast channels and slow channels.
Term
Chemical messengers
Definition
A form of indirect intercellular communication. The most common form of intercellular communication. Includes paracrines, neurotransmitters, and hormones. Lipophilic or lipophobic. Classified into amino acids, amines, peptides/proteins, steroids, and eicosanoids. Acetylcholine and nitric oxide do not fall into any of these categories.
Term
Chemistry
Definition
A defining idea of biology.
Term
Cholera
Definition
A bactera that lives in the intestinal lumen. Releases toxins that cause excessive release of ions into the intestinal lumen. Excessive water diffuses into the lumen. Transmitted by water contaminated with the diarrhea. Treated with lots of clean water and electrolytes, and an anti-cholera pill. People can die of cholera.
Term
Cholesterol
Definition
A four-ring lipid molecule. Steroids are derived from it.
Term
Chondrocytes
Definition
The cells found in cartilage. Embedded in lacunae. Nutrients are carried through them by diffusion, which makes healing slow.
Term
Chronobiology
Definition
The study of timescales in biology. Rhythms include ultradian, circadian, and infradian.
Term
Circadian
Definition

aka Diurnal

A biological rhythm with a period of one day. Present in essentially all physiological processes. Controls by gene expression, regulation of enzyme activities, neural function, and hormone secretion. Co-ordinates sleep, nutrient supply, and activity patterns within metabolic patterns at diferent times of the day. Disrupting circadian rhythms causes a wide spectrum of health problems and premature aging. Controlled by the suprachiasmatic nucleus.

Term
Clinical depression
Definition
Feelings of sadness that extend for longer than is normal, interfering with daily life. Lack of pleasure, anxiety, sleep problems, decreased energy, feelings of sadness, hopelessness, worthlessness, and guilt. Can complicate other diseaes. Insufficient levels of serotonin. People can die from suicide. Medications increase function of serotonin, dopamine, and/or norepinephrine synaptic signals. In PET scans the brain has reduced activity.
Term
Clinical trials
Definition
Tests conducted on humans on the effect of a drug after it is proven to cause little or no harm to test animals. It is tested to see if there are any ill effects on humans, if it is an effective drug, and how it compares to other treatments. Only volunteers are used. Done in hospitals, clinics, universities, and private companies. Ethics are closely monitored. Includes non-intervention studies and intervention studies.
Term
Closed head injury
Definition
Brain injury when the head suddenly changes motion, forcing the brain to ricochet within the skull. The brain may be cut or bruised on sharp ridges and edges on the inside of the skull. Common in motor vehicle accidents.
Term
Clotting factors
Definition
A paracrine protein that stimulates the formation of blood clots.
Term
Cocaine
Definition
A naturally occuring physiological agonist. Blocks the re-uptake of dopamine.
Term
Codeine
Definition
An addictive painkiller drug found in Tylenol 1. Found in the opium poppy. When ingested it is converted to morphine.
Term
Collagen fibres
Definition
A type of protein fibre in connective tissue matrix. Strong and rope-like. Has great tensile strength. Found in the lacunae of hyaline cartilage and fibrocartilage, in the matrix of bone, and in the dermis.
Term
Collective medicine
Definition
A new dimension in medical and healthcare practices. Includes EcoHealth and One Health.
Term
Collectivism
Definition
A cultural philosophy that health is an aspect of the needs and wants of a community of people rather than indiiduals. Found in some regions of Africa.
Term
Columnar
Definition
A shape of epithelial tissue. Elongated, column-shaped cells. Includes simple and stratified.
Term
Community
Definition
All the species living in an ecosystem.
Term
Compression fracture
Definition
A fracture in the vertebrae caused by low bone density. Decreases the height of the person.
Term
Concrete operational
Definition
The life stage between 7 and 11 years of age. Abstract thought and logic develop. Can perform mental operations and manipulate objects. Unable to distinguish between mind and body.
Term
Confounding variable
Definition
A variable that has not been controlled in a controlled experiment. If present, we cannot say for sure that the variable is what is causing the difference between treatments.
Term
Connective tissue
Definition
A tissue type. The most abundant and widely distributed tissue in the body. Storge of fat, transportation, and support. Binds the body together. Cells are embedded in matrix; most of the connective tissue is matrix. Includes connective tissue proper and specialized connective tissue.
Term
Connective tissue proper
Definition
A type of connective tissue. Includes loose and dense connective tissue.
Term
Connexon
Definition
A membrane protein that forms gap junctions.
Term
Control and Communication Network (CCN)
Definition
A biological concept of health. The logic unit of the human adult. Distributed throughout the body, but anatomical linkages may be obscure. The locus of health in human adults; aging and diseases are caused by compromise of the structure or function of the CCN. Includes the central nervous system, peripheral nervous system, endocrine, and local support and defense systems. Controls and co-ordinates the function of all physiological systems and individual organs, including organ systems and organs within the network. Always working constantly. Eah component has many functions and there is redundancy in the system. Components not separate from one another. Communication is chemical based from cell to cell. The intergrator of inputs to health and the seven dimensions of health.
Term
Control centre
Definition
A component of a negative feedback mechanism. Receives signals from the receptors and integrates the information and sends a signal to the effector. In most negative feedback loops, it is the brain.
Term
Control group
Definition
The group in a controlled experiment that lacks the treatment.
Term
Controlled experiment
Definition
An experiment where there can be only one explanation for the results. There is a control group and an experimental group which differ by one variable.
Term
Corpus callosum
Definition
A band of white matter that connects the two hemispheres of the cerebrum. Allows the hemisphere to communicate with each other.
Term
Corticosteroid-binding globulin
Definition
A carrier protein that transports cortisol.
Term
Cortisol
Definition
A lipophilic hormone. Carried in the blood by corticosteroid-binding globulin. Supresses pain.
Term
Cranial cavity
Definition
A division of the dorsal body cavity. Contains the brain.
Term
Critical thinking
Definition
Is the information consistent with information from other sources? Is it reliable? Is it biased? Was it obtained through proper scientific procedure? Were the data interpreted correctly? Are there other possible explanations for the results?
Term
Cuboidal
Definition
A shape of epithelial tissue. Cube-shaped cells. Incldues simple and stratified.
Term
Culture
Definition
Non-genetic transmission of behavioural styles to the next generation. One of the things that sets humans apart from other species. A set of social influences that produce an integrated pattern of knowledge, belief, and behaviour. Social influences are less pronounced in other species. We have rituals and arts. There are many different human cultures, but they all share certain common elements, such as love for children and the need to belong to a group. Affects ethnicity, physical activity, healthcare, smoking/drinking habits, transportation, and nutrition.
Term
Cutaneous membrane
Definition

Skin

A type of membrane. Covers the outside of the body. Unlike other membranes, it is thick, relatively waterproof, and relatively dry.

Term
Cuticle
Definition
A part of a hair. The outermost layer of the strand. A single layer of thin, flat, scale-like cells packed with keratin. Abrasion of this part causes frizzy hair and split ends.
Term
Cyclic adenosine monophosphate (cAMP)
Definition
Adenylate cyclase converts it from ATP. Activates protein kinase A. Deactivated by cAMP phosphodiesterase.
Term
Cyclic guanosine monophosphate (cGMP)
Definition
A second messenger that guanylate cyclase converts from GTP. Activates protein kinase G.
Term
Cyclooxygenase
Definition
Catalyzes the conversion of arachidonic acid into prostacyclin, prostaglandin, or thromboxane in the cyclooxygenase pathway. Aspirin inhibits its activity, reducing production of blood-clotting and inflammation messengers.
Term
Cyclooxygenase pathway
Definition
Arachidonic acid is converted into prostacyclins, prostaglandins, and thromboxanes, catalyzed by cyclooxygenase.
Term
Cystic fibrosis
Definition
Generally a genetic disorder, but there are other factors. Not enough fluid is released into the intestinal lumen and lungs. Can cause pneumonia or gastrointestinal problems.
Term
Cystic fibrosis conductance regulator (CFTR)
Definition
A channel protein involved in maintaining intestinal lumen water levels. A chloride ion transporter. Affected by cholera, listeria, salmonella, and cystic fibrosis.
Term
Cytokines
Definition
A paracrine secreted by immune cells. Co-ordinates the body's defense against infections. Sometimes it can act like a hormone.
Term
Death
Definition
When the CCN fully shuts down.
Term
Deductive reasoning
Definition
A general statement that leads logically to one or more conculsions.
Term
Deep brain stimulation (DBS)
Definition
A surgical treatement involving the implantation of a "brain pacemaker" which sends electrical impulses to specific parts of the brain. Approved for treatment of some mental illnesses and neurological disorders.
Term
Deeper Blue
Definition
A computer built in 1997 which can defeat the world's champion chess players. Nowadays the same amount of computing power can fit inside a cell phone.
Term
Dendrites
Definition
A part of a neuron. Highly branched extensions. Increases the surface area for reception of incoming impulses.
Term
Dense connective tissue
Definition
A type of connective tissue proper. Large amount of protein fibres tightly woven, forming strong bonds. Includes ligaments, tendons, and dermis.
Term
Dependency
Definition
The life stage after healthspan ends. When you require someone to take care of you.
Term
Dependent variable
Definition
Graphed on the y-axis.
Term
Depolarization
Definition
In action potential, the charge difference across the axon membrane is reduced by sodium ions entering the axon. When it reaches its threshold, the gates of sodium channels open, creating a net positive charge. Followed by repolarization.
Term
Dermis
Definition
A type of dense connective tissue proper. The thicker layer in the skin found below the epidermis. Contains blood vessels, nerves, sweat glnds, and oil glands. Does not shed as the epidermis does. Lower dermis contains collagen and elastic fibres, making skin stretchy.
Term
Descending tracts
Definition
A cluster of myelinated axons in the white matter of the spinal cord that bring information from the brain to the body.
Term
Diabetes
Definition
A leading cause of death in Canada. 3.4% of deaths. When not enough insulin is produced by the pancreas, or the body is unable to use insulin. Without insulin, when a meal is digested blood sugar is not absorbed by the liver, causing blood sugar levels to rise to a point where it can cause damage to the eyes, kidneys, nerves, and blood vessels. Treated with diet, exercise, medication, and sometimes insulin injections.
Term
Diaclyglycerol (DAG)
Definition
Released along with IP3 from PIP2, catalyzed by phospholipase C, in the phosphatidylinositol system. Activates protein kinase C.
Term
Diaphragm
Definition
A sheet of muscle that separates the thoracic and abdominal body cavities in the ventral body cavity.
Term
Digestive system
Definition
Physical and chemical breakdown of food. Absorbs, processes, and stores food.
Term
Disease
Definition
Caused when the function of the CCN is compromised.
Term
Docking
Definition
A form of direct intercellular communication. Membrane proteins of two cells interact without detaching. Found in mobile cells such as immune cells.
Term
Dopa decarboxylase
Definition
One of the enzymes which catalyes the conversion of tyrosine into dopamine in the cytosol. The other is tyrosine β-hydroxylase.
Term
Dopamine
Definition
A catceholamine neurotransmitter. The reward neurotransmitter. Regulates emotions and motor control. Released while anticipating a real-life reward. If the reward is a maybe, more dopamine is released, making the individual more driven. Synthesized from tyrosine in the cytosol, catalyzed by tyrosine β-hydroxylase and dopa decarboxylase.
Term
Dopamine β-hydroxylase
Definition
The enzyme which converts dopamine into norepinephrine in vesicles.
Term
Dorsal body cavity
Definition
A main body cavity near the back of the body. Divided into the cranial and spinal cavities.
Term
Double standards
Definition
The evaluation, treatment, or measuremet of identical behaviours, traits, or situations by different means.
Term
Double-blind test
Definition
When neither the participants nor the researchers in a clinical trial know which treatment is the placebo and which is the real drug. Prevents bias.
Term
Down-regulation
Definition
When the cell decreases the number of receptors. Occurs when the cell is exposed to higher levels of messenger for extended periods. Cell becomes less receptive to the messenger.
Term
Drosophilia melanogaster
Definition
A test animal. Fruit flies. Complex life cycle. Sensitive to environmental conditions.
Term
Dual energy X-ray absorptiometry (DEXA)
Definition
A scanning technology that measures bone density. Less radiation than an X-ray. Usually scans the lower spine, hip, and wrist. Scores between -1.0 T and -2.8T are indicative of osteoporosis.
Term
Dualism
Definition
The idea that the mind is "nonmaterial" and the body is "material", separate entities. The mind was thought to communicate with the body through the pineal gland in the mid-brain. At death it was thought that the soul left the body.
Term
Dura mater
Definition
A tough leathery outer layer of the meninges. Attached to the arachnoid.
Term
Early aulthood
Definition
The stage of life between ages 17 and 40. Transition out of adolescence. Forges identiy, assumes roles and responsibilities of adulthood. The "prime of life". Many transitions occur: graduation, career, pregnancy, marriage, childbirth, divorce, parenthood. Transitions have different effects on different individuals.
Term
EcoHealth
Definition
An aspect of collective medicine. An association whose mission is to strive for sustainable health of people, wildlife, and ecosystems by promoting discovery, understanding, and transdisciplinarity. Human and animal physical and mental health are inextricably linked.
Term
Ecosystem
Definition
The community of organisms in the environment as well as the environment itself.
Term
Educational support
Definition
A support that may lead to a health promotion. Promotion of learning.
Term
Effector (homeostasis)
Definition
A component of a negative feedback loop. Recieves a message from the control centre and activates a mechanism to respond to change in the environment.
Term
Effector (nervous system)
Definition
Muscles or glands. Receive signals from motor neurons and contract or secrete product.
Term
Egocentric
Definition
Self-centered. Sees things from only their own perspective.
Term
Eicosanoid
Definition
A chemical classification of chemical messengers. Paracrines, produced in almost every cell of the body. Lipophilic. Includes prostacyclins, prostaglandins, leukotrines, and thromboxanes. Derived from arachidonic acid in the cytoplasm.
Term
Elastic cartilage
Definition
A type of cartilage. Found in the external ear. More flexible than hyaline cartilage. Provides strength and elasticity. Matrix contains elastic fibres.
Term
Elastic fibres
Definition
A type of protein fibre found in connective tissue matrix. Random coils. Can stretch and recoil like a spring. Found in skin, lungs blood vessels, and elastic cartilage.
Term
Elderly
Definition
The stage of life after age 60. The portion of the population that is elderly has increased in recent years and is projected to increase further. Elderly women are more likely to have arthritis and elderly men are more likely to have cardiovascular diseases.
Term
Emergent properties
Definition
Properties that cannot be reduced to the sum of their component parts. Many of the things which mae us uniquely human are emergent properties.
Term
Emerging adult
Definition
A new category of life-stage in humans between teh ages of 18 an 25. The brain has not yet reached full maturation.
Term
Emotional health
Definition
One of the seven dimensions of health. Ability to effectively and appropriately express emotions, self-esteem, self-efficacy, trust, and love.
Term
Encephalitis
Definition
Inflammation of the brain. Can be caused by meningitis.
Term
Endocrine gland
Definition
A gland which excretes products into the space just outside of epithelial cells. Lacks a duct. Products are hormones, which are carried into the bloodstream.
Term
Endocrine system
Definition
Part of the CCN. Regulates and integrates body functions via hormones. Provides slower and longer-lasting homeostasis responses. Includes the exocrine system with endocrine-like activity. Lacks direct anatomical link between secretory and target cells; hormones travel in the bloodstream. Communicate by enzyme and G protein-linked signal transduction. Considerably slower than the nervous system. Secretory cells are endocrine cells. Target cells are all cells of the body. Messengers are hormones.
Term
Endothelial cell
Definition
One of the cells in the blood-brain barrier. Tube-shaped blood capillary cells. The first call that molecules must pass through to reach the brain. Contains the lumen of the blood vessel.
Term
Energy distribution system
Definition
An organ system. Stores energy, insulates, and cushions organs. Adipose tissue.
Term
Enhancement medicine
Definition
A new dimension in medical and healthcare practice. Includes Botox, Viagra, cosmetic surgery, erythropietin, nootropics, laser vision enhancement, fertility technologies, liposuction, anabolic steroids, and hallucinogens. There is lots of demand for enhancement medicine. More rewarding to physicians; not avoiding suffering, insted making people feel better.
Term
Environment
Definition
One of the inputs to health.
Term
Environmental health
Definition
One of the seven dimensions of health. Comfortable lighting, noise level, and personal space. Appreciation of external environment and the role individuals play in preserving, protecting, and improving it. Biophilia.
Term
Environmental support
Definition
A support which my lead to a health promoton. Rules and governing attitudes that support decisions to change.
Term
Enzyme-linked receptors
Definition
Receptors for lipophobic messengers that are also enzymes. The enzyme is only active when the messenger is bound to it. Includes tyrosine kinase and guanylate cyclase.
Term
Ependymal cells
Definition
Cells in the central nervous system. Line the ventricles and produce cerebrospinal fluid.
Term
Epidemiological study
Definition
A non-intervention study with a large number of participants. Researchers look at patterns that occur in large populations instead of testing them in a controlled experiment.
Term
Epidemiology
Definition
The study of disease patterns in populations, mortality, morbidity, prevalance, incidence, and risk.
Term
Epidermis
Definition
The thinner outer layer of the skin overtop of the dermis. The very outer layer is composed of dead cells which are shed at a rate of 30 - 40 thousand cells per minute. These dead cells can swell with water if soaked for extended periods (such as a long bath), causing wrinkling. New cells are generated by rapidly dividing cells underneath the dead cells and then pushed upwards. 2 - 4 weeks later, as they die, the cytoplasmic contents are replaced with keratin. The epidermis lacks blood vessels; nutrients diffuse to them from the dermis from tissue fluid. Takes up melanin from melanocytes, giving epidermis a certain colour.
Term
Epinephrine
Definition

aka Adrenaline

A lipophobic catecholamine hormone. Synthesized from norepinephrine in vesicles, catalyzed by PNMT.

Term
Epithelial tissue
Definition
A tissue type. Covers body surfaces, lines body cavities and organs, forms glands. Has a free surface and a basement membrane. It has three shapes: squamous, cuboidal, and columnar. Includes simple and stratified tissue.
Term
Estrogen
Definition
A lipophilic sex hormone.
Term
Eukarya
Definition
A domain of life. Eukaryotes. Includes multi-cellular organisms.
Term
Eukaryote
Definition
Includes the domain of Eukarya. Contains a nucleus and organelles. Divided into four kingdoms: protists, fungi, plants, and animals.
Term
Evidence based medicine
Definition
An algorithm is used to treat patients. A mixture of research evidence, clinical data from the patient, and the patient's personal values and culture to reach an optimal decision.
Term
Evolution
Definition
A defining idea of biology.
Term
Evolutionary medicine
Definition
A new dimension in medical and healthcare practices. Knowledge about evolution providing physicians with an integrative framework that links bits of knowledge. Views of bodies as shaped by evolutionary processes.
Term
Ex vivo research
Definition
Experiments done on dead cells or organisms.
Term
Excitatory synapse
Definition
A synaptic signal that opens sodium channels, generating an action potential in the postsynaptic neuron. Contributes to summation.
Term
Exocrine gland
Definition
A gland which excretes products into a duct leading to a body surface, cavity, or organ. Products include digestive enzymes, milk, oil, and sweat.
Term
Exocrine system
Definition
Part of the endocrine system.
Term
Experimental group
Definition
The group(s) in a controlled experiment that have treatment.
Term
Extracellular fluid
Definition
All cells in the body are surrounded by this fluid.
Term
Fast channels
Definition
Channel-linked receptors where the lipophobic messenger binds directly to the channel, opening it. Response is a few milliseconds.
Term
Fibroblasts
Definition
Cells in connective tissues that produce the protein fibres of the matrix. Repair tears in body tissue. When skin is cut, they produce collagen which closes the wound, covering the damage, and providing a surface for new skin cells to grow over
Term
Fibrocartilage
Definition
A type of cartilage. Has fewer chondrocytes than hyaline or elastic cartilage. Forms cushioning layer in the knee joint and in the shock-absorbind discs between vertebre of the spine. Can withstand pressure. Lacunae contains collagen fibres.
Term
Financial support
Definition
A support that may lead to a health promotion. Monetary incentives for healthful decisions.
Term
First degree burn
Definition
A burn whhich goes only as deep as the epidermis.
Term
First messenger
Definition
The original messenger in signal transduction. May induce the release of a second messenger.
Term
Follicle
Definition
A part of a hair. It is in the dermis or hypodermis. The hair root is embedded in it. Nerve endings surround it, making hairs sensitive to touch. Secretes sebum, which makes the hair soft and pliant. Arrector pili muscles are attached to the follicle. Bacterial infection of follicles can lead to acne.
Term
Formal operational
Definition
The life stage after 12 years of age. Abstract thought, imagination, and reasoning are devloped.
Term
Formed elements
Definition
The cells found int he blood. Include red blood cells, which blood cells, and platelets.
Term
Free surface
Definition
The surface of epithelial tissue that is specialized for protection, secretion, or absorption.
Term
Frontal lobe
Definition
A lobe of the cerebrum. Includes the prefrontal cortex, premotor cortex, and primary motor area.
Term
Fungi
Definition
A kingdom of Eukarya.
Term
G protein
Definition
Has three subunits, α, β, and γ. When inactive, it binds to GDP. When bound to a messenger, the α and GDP fall off, and it binds to GTP. The α subunit then causes cell responses. Includes stimulatory G proteins and inhibitory G proteins. Effect amplifier enzymes.
Term
G protein-linked receptor
Definition
Receptors that activate G proteins.
Term
G protein-regulated enzyme
Definition
Enzymes activated by G proteins. Produce second messengers in the cytosol. Second messengers produced include cAMP, cGMP, and the phosphoatidylinositol system.
Term
Gamma-aminobutyric acid (GABA)
Definition
A gamma amino acid chemical messenger. Synthesized from glutamate within the neuron they are transmitted from. Synthesis catalyzed by glutamic acid decarboxylase. An inhibitory neurotransmitter of dopamine. Morphine blocks its release.
Term
Ganglia
Definition

Singular "ganglion"

Clusters of cell bodies outside the central nervous system.

Term
Gap junction
Definition
A form of direct intercellular communication. Cell junctions that are doors between the cytoplasm of the two cells, allowing for exchange of certain small molecules and ions. Electrically and metabolically couples the cells. help with contractions. Formed from connexons. Found in the smooth muscle, cardiac muscle, blood vessel, and bone cells.
Term
Genes
Definition
A defining idea of biology.
Term
Genetics
Definition
One of the inputs to health.
Term
Gland
Definition
Epithelial tissues that secrete a product. Include exocrine and endocrine glands.
Term
Glucocorticoids
Definition
Drugs that can impair calcium deposition in bones.
Term
Glutamate
Definition
An amino acids chemical messenger that is derived by adding amine groups to certain Krebs cycle intermediates.
Term
Glutamic acid decarboxylase
Definition
Catalyzes the synthesis of GABA from glutamate.
Term
Glycine
Definition
An amino acid neurotransmitter. Synthesized from a glycolytic intermediate, 3-phosphoglycerate.
Term
Goblet cells
Definition
Columnar epithelial cells in the small intesetine which secrete mucus to ease the passage of food.
Term
Ground substance
Definition
A component of matrix in connective tissues. May be solid, fluid, or gelatinous. Secreted by connective tissues or other cells.
Term
Growth factor
Definition
A paracrine protein that stimulates the proliferation and differentiation of cells.
Term
Guanosine diphosphate (GDP)
Definition
Binds to inactive G proteins.
Term
Guanosine triphosphate (GTP)
Definition
Binds to activated G proteins that have messenger bound to them. Guanylate cyclase catalyzes its conversion into cGMP.
Term
Guanylate cyclase
Definition
An enzme-linked receptor that catalyzes the conversion of GTP into cGMP.
Term
Hair
Definition
A part of the integumentary system. Grows all over the body, except on the lips, palms of the hands, and soles of the feet. Hair is dead cells filled with keratin packed into a long column. Head hair provides protection from UV radiation, nose and ear hair protects the orificies from particles entering it. Hair has four parts: shaft, root, follicle, and cuticle. Hair grows for 2 - 6 years, then stops.
Term
Half-life
Definition
The time it takes for half of hormone in the blood to be degraded. For free lipophilic hormone, it is a few minutes. For lipophilic hormones bound to carrier protein it is a few hours. Lipophobic hormones have shorter half-lives.
Term
Handicap
Definition
Inability to perform one's normal societal roles; usually resulting from impairment or disability.
Term
Health
Definition

"Wholeness"

A  dynamic, ever-changing state of complete physical, metal, and social well-being. Not merely in the absence of disease or infirmity.

Term
Health promotion
Definition
An educational, organizationa, political, financial, or environmental support that enhances and increases the changes of healthy lifestyle choices and helps people change negative health attitudes and behaviours.
Term
Healthspan
Definition
The amount of time a person has when they can live independently. Usually shorter than lifespan. The goal of most individuals and societies is to maximize healthspan.
Term
Healthy behaviour
Definition
Behaviour performed by an individual regardless of their health status, as a means of protecting, promoting, or maintaining health.
Term
Heart diseases
Definition
A leading cause of death in Canada. 22.4% of deahts.
Term
Height
Definition
A biomarker for spinal osteoporosis. Needs to be measured regularily to be useful. Varies in a circadian rhythm due to fluid levels between vertebral discs. After a long day the space between vertebrae is smaller, and sleep rehydrates them. A person is slightly shorter before going to bed than they are waking up. This variability limits the usefullness of height as a biomarker for osteoporosis, unless charted at the same time of day over many years.
Term
Hemispheres
Definition
The two halves of the cerebrum. Separated by the longitudinal fissure. Directs movement from opposite sides of the body, process information slightly differently, and are specialized for slightly differen mental functions.
Term
Hippocampus
Definition
Part of the limbic system. Turns short-term memories into long-term memories.
Term
Hippocratic Oath
Definition
An oath that all medical students must take when they become practicing physicians. Acknowledge that patients are human beings and that prevention of illness is preferable to curing already existing diseases.
Term
Histamine
Definition
An important paracrine that is secreted by mast cells. Responsible for symptom of allergic reactions such as inflammation.
Term
Holism
Definition
A perspective in biology. Focused on the overall emergent functions of a system. An approach to health that considers the whole being rather than individul components. Found in many eastern cultures.
Term
Homeostasis
Definition

"To stay the same"

The relatively constant, dynamic, and self-correcting internal environment of an organism. Life can only exist within certain limits, so organisms keep their body systems within these limits. The organ systems of multicellular, multi-organ organisms are constantly adjusting their functioning in response to changes in the internal and external environment. Relies on communication through the nervous and endocrine systems. Uses negative feedback mechanisms. Failure results in illness. Maintained by the CCN.

Term
Hormone
Definition
A type of chemical messenger. Secreted by endocrine glands. Diffuses into the blood stream and travels to target cells which are far away. Only target cells with a specific receptor to the hormone. Includes amines, steroids, peptides, and proteins. Includes insulin, neurohormones, vasporessin, and epinephrine.
Term
Hormone response element (HRE)
Definition
Regions of the DNA to which lipophilic hormone-receptor complexes bind, activating or deactivating genes for proteins.
Term
Humoral theory
Definition
Hippocrates associated the mind and body as one unit in balance with the four humors: yellow bil, phlegm, blood, and black bile. Illness was said to be as a result of an imbalance in the humours. Each humor is associated with seasons, personalities, and illnesses.
Term
Hyaline cartilage
Definition

aka Gristle

A type of cartilage. The most abundant type of cartilage. Found at the ends of long bonds, allowing one bone to slide easily over the other, as well as in the nose, ribs, larynx, and trachea. Provides support and flexibility. Lacunae contains fibres and bluish-white gel-like ground substance.

Term
Hydroxyapatite
Definition
An insoluble deposit of calcium and phosphate found in the matrix of bone tissue. Not compressible. The more calcium in the bones, the denser it is.
Term
Hyperthermia
Definition

aka Heat stroke

When the mechanisms for lowering body temperatures fails. Can occur in situations were perspirtion fails to lower temperature, such as a hot tub or very humid weather. Symptoms are confusion, dizziness, irregular heartbeat, low blood oxygen levels, cease of liver function, and when severe, unconsciousness and death. Body temperatures over 42°C are fatal.

Term
Hypodermis
Definition

aka Subcutaneous layer

A layer of loose connective tissue underneath the skin. Cushions from blows and prevents extreme changes in body temperatures. Contains half of the body's fat stores. In infants it covers the whole body, giving the appearance of "baby fat". As we mature fat redistributes. In women it goes to breasts, hips, and thighs. In both sexes it goes to the belly and lower back regions. In the elderly the hypodermis becomes less fatty, resulting in wrinkling.

Term
Hypothalamus
Definition
The region of the brain which is the control centre for negative feedback mechanisms controlling homeostasis in body temperature, heart rate, blood pressure, breathing rate, and food intake. Plays a role in sex drive, pain, pleasure, fear, and anger. Includes the suprachiasmtic nucleus.
Term
Hypothermia
Definition
When the mechanisms for raising body temperature fails. Symptoms include giddiness and confusion. At 33°C the person will lose consciousness. At 30°C blood vessels are completely restricted and temperature-regulting mechanisms fully shut down. Death soon follows. Treated by warming the body, including dialysis mchines that warm the blood and pump it back into the body.
Term
Hypothesis
Definition
A possible answer to a question posed in scientific method. Cannot be proven to be true, only proven to be untrue.
Term
Illness
Definition
Occurs when homeostasis fails.
Term
In silico research
Definition
Simulations on a computer or with chemicals in a lab. Used for mechanical or chemical techniques. Lots of research is done in silico.
Term
In vitro research
Definition
Experiments done on cell cultures.
Term
Incidence
Definition
The number of new causes of a disease occuring within a defined time interval.
Term
Independent variable
Definition
Graphed on the x-axis.
Term
Individual
Definition
A single organism composed of organ systems. Comprises populations.
Term
Indiviualism
Definition
A culture philosophy that health is an aspect of the individual.
Term
Inductive reasoning
Definition
Facts are accumulated through observation until the sheer weight of evidence allows some logical general statement to be made.
Term
Inflammation
Definition
Redness and swelling. Caused by the paracrine histamin, released during allergic reactions.
Term
Influenza and pneumonia
Definition
A leading cause of death in Canada. 2.5% of deaths.
Term
Informed consent
Definition
All participants of clinical trials must consent to all the possible harmful effects an risks of treatment. Must be mentally capable of understanding the treatment and risks.
Term
Infradian
Definition
A biological rhythm with a period greater than one day. Includes menstral cycle and hibernation.
Term
Inhibitory G proteins
Definition
G proteins that deactivate enzymes.
Term
Inhibitory synapse
Definition
A snaptic signal that opens ion channels, reducing action potential in the postsynaptic neurons. Contributes to summation.
Term
Inositol triphosphate (IP3)
Definition
Released along with DAD from PIP2, catalyzed by phospholipase C in the phosphatidylinositol system.
Term
Inputs to health
Definition
Genetics, environment, and lifestyle.
Term
Insulin
Definition
A lipophobic protein hormone released by the pancreas. Target cells all over the body. Controls metabolism.
Term
Integrative medicine
Definition
A new dimension in medical and healthcare practice. A blance between the seven pillars of health: physical, mental, social, emotional, environmental, occupational, and spiritual health.
Term
Integument
Definition
Outer covering.
Term
Integumentary system
Definition
Protects underlying tissues, provides skin sensation, helps regulate temperature, synthesizes vitamin D. Includes skin, hair, nails, sweat glands, and oil glands.
Term
Intercellular communication
Definition
Direct or indirect.
Term
Interneuron
Definition

aka Association neruons

99% of neurons in the body are interneurons. Located between sensory and motor neurons. Found in the brain and spinal cord. "Decide" on the appropriate response to send to motor neurons.

Term
Intervention studies
Definition
A type of clinical trial. Subjects are given a medicinal treatment or a placebo. By comparing data from the treatment and control groups, these experiments can be used to predict and prove the cause and effects of medicinal substances. Includes double-blind clinical trials.
Term
Intestinal lumen
Definition
Normal fluid levels are maintained by taking ions in and out of the lumen. Water diffuses in or out accordingly. Excessive water in the intestinal lumen causes diarrhea.
Term
Inuksuk
Definition
A metaphor for the hidden complexity of living organisms.
Term
Ion channels
Definition
Gap junctions in nerve axons that allow transfer of sodium and potassium ions. Some are constantly open and some can close. Includes sodium-potassium pumps.
Term
Keratin
Definition
A waterproof protein. As epidermis cells die, the cytoplasmic contents are replaced with keratin. Plays a vital role in preventing excessive water loss from underlying tissues. The cells of the cuticle of a hair are filled with keratin. The cells of nails are hardened by keratin.
Term
Keratinocytes
Definition
Cells in the skin which produce keratin.
Term
Lactation
Definition
Takes up a lot of calcium from the bones. After lactation, bone density returns to normal.
Term
Lacunae
Definition
The matrix of cartilage. Chondrocytes are embedded in it. Gelatinous and contains protein fibres.
Term
Leukotrienes
Definition
An eicosanoid synthesied in the lipoxygenase pathway.
Term
Levels of life
Definition
Molecule < Cells < Tissue < Organ < Organ system < Individual < Population < Community < Ecosystem < Biosphere
Term
Life
Definition

1. Contains nucleic acids, proteins, carbohydrates, and lipids.

2. Composed of cells.

3. Grow and reproduce, generating new individuals.

4. Uses energy and raw materials.

5. Detects and responds to stimuli from the environment.

6. Maintains homeostasis.

7. Adapt and evolve new traits.

Term
Lifespan
Definition
The amount of time a person has to live. May have to make decisions that balance it with healthspan. Lifespan may be calculated based on factors such as weight, exercise, stress, sleep, education, blood pressure, smoking, and age of parents.
Term
Lifestyle
Definition
One of the inputs to health. Includes healthcare behaviours.
Term
Ligament
Definition
A type of dense connective tissue proper. Attach bones to bones.
Term
Ligand
Definition
A molecule that reversibly binds to proteins.
Term
Ligand-gated channels
Definition
Ion channels that close or open when bound to ligands. Includes channel-linked lipophobic hormone receptors.
Term
Limbic system
Definition
A group of structures in the brain that produce emotions and memories. Allows us to feel rage, pain, fear, sorrow, joy, and sexual pleasure. Gives us short-term and long-term memory. Parts include the hippocampus, amygdala, and olfactory bulb.
Term
Lipophilic
Definition

aka Hydrophobic

Lipid-soluble. Cannot dissolve in water. Transported through the blood with a carrier protein; an equilibrium is established between hormone bound to carrier protein and free hormone. Only free hormone can attach to receptors. Lipophilic chemical messengers can readily cross the plasma membrane. Diffuses into the target cell and binds to receptors in the cytosol. In the nucleus the hormone-receptor complex binds to HRE, activation or deactivating regions of the DNA. No storage method; produced on demand and released immediately. Response is slow and long. Have a long half-life.

Term
Lipophobic
Definition

aka Hydrophilic

Water-soluble. Dissolves in water. Stored in vesicles. Lipophobic hormones dissolve into the bloodstream. Lipophilic chemical messengers can readily cross the plasma membrane. They cause signal transduction by channel-linked, enzyme-linked, or G protein-linked receptors. Response is fast and short. Have a short half-life.

Term
Liposuction
Definition
A procedure that vaccums fat out of the hypodermis to reshape the body. An incision is made through the skin into which  tube is inserted. The tube is wiggled to loosen the fat cells which are then sucked out through the tube. Only a small amount of fat may be removed this way. Fat does not usually return to these areas becuse fat cells have been removed. May produce blood clots which could travel to the lungs, leading to death.
Term
Lipoxygenase
Definition
Catalyzes the conversion of arachidonic acid into leukotrienes in the lipoxygenase pathway.
Term
Lipoxygenase pathway
Definition
Arachidonic acid is converted into leukotrienes, catalyzed by lipoxygenase.
Term
Local support and defense system
Definition
Part of the CCN. Includes maintenance and support, adaptation and repair, resident defense, and migrant defense systems.
Term
Logic units and information flow
Definition
A defining idea in biology.
Term
Long-term memory
Definition
Memories for hours, days, or years. Seemingly limitless amounts of information stored. The amygdala gives us long-term memory.
Term
Longitudinal fissure
Definition
A deep ridge between the two lobes of the cerebrum.
Term
Loose connective tissue
Definition
A type of connective tissue proper. Fewer and more loosely woven protein fibres than dense tissue. Includes areolar and adipose tissue.
Term
Lymphatic system
Definition
Returns fluids to the bloodstream. Protects against infection and disease.
Term
Macrophage
Definition
A type of cell in the skin which fights infections.
Term
Maintenance and support system
Definition
Part of the local support and defense system.
Term
Malignant neoplasms
Definition
The leading cause of death in Canada. 29.3% of deaths.
Term
Mammal
Definition
A group within the subgroup of vertebrates. Have hair, feed young with milk produced in mammary glands. Humans belong to this group.
Term
Mast cells
Definition
Cells throughout the body that secrete histamine.
Term
Matrix
Definition
Extracellular substance in which connective tissues are embedded. Includes protein fibres and ground substance.
Term
Mechanistic viewpoint
Definition
An aspect of dualism that views the body as a machine that is understandable only in terms of its parts.
Term
Mechanosignals
Definition
A form of indirect intercellular communication. Cells are connected with a network of filamentous proteins that cells can pull on, communicating with each other.
Term
Medulla oblongata
Definition
Part of the brainstem. Contains autonomic centres for heart rate and digestive activities, and relays information to the thalamus. Connects the spinal cord to the brain.
Term
Melanin
Definition
Colour pigment in the skin. Produced by melanocytes. There are two kinds: yellow-to-red and black-to-brown. it is taken up by the surrounding epidermal cells, colouring the skin. It absorbs UV radiation, protecting the lower epidermis and dermis.
Term
Melanocytes
Definition
Cells in the skin which make melanin. Everyone has around the same amount of melanocytes, but differing amounts of melanin produced.
Term
Melanoma
Definition
A type of skin cancer. Caused by environment and lifesyle. the most rare and most dangerous type of skin cancer. Unlike other forms of skin cancer, it may metastasze. Survival rate is 90% before spreading and 14% after. Melanoma tumours are mottled and may appear brown, black, white, or blue in colour. They have an asymmetrical shape with a diffuse, unclear border. Grow to more than 5 mm in diameter.
Term
Membrane
Definition
Sheets of epithelial tissues supported by connective tissue that cover organ and body cavity surfaces. Incldues mucous, serous, synovial, and cutaneous membranes.
Term
Meninges
Definition
Protective connective tissue covering the central nervous system. Include dura mater, arachnoid, and pia mater.
Term
Meningitis
Definition
An inflamation of the meninges caused by bacteria and viruses. Infection can spread, causing encephalitis. Contracted through saliva. Antibacterial treatments and vaccines.
Term
Mental health
Definition
One of the seven dimensions of health. Ability to think clearly, reason objectively, analyze critically, use brain power effectively to meet life's challenges, learn from successes and failures, and make responsible decisions.
Term
Mental illness
Definition
Illnesses in the brain. Include Alzheimer's disease, depression, social anxiety disorder, schizophrenia, bipolar disorder, obsessive compulsive disorder, Tourett syndrome, panic disorder, attention deficit disorder, Parkinson's disease, body dysmorphic disorder, post-traumatic stress disorder, and eating disorders. Harmful dysfunctions stemming from the abnormal function of cells in the brain. Used to be treated with trepanation, shunning, punishment, asylums, or exorcisms. Nowadays treated with drug therapies, talk therapies, irradiation, surgeries, and tissue implants.
Term
Meta-analysis
Definition
The analysis of the results of many research studies together. The most reliable form of research.
Term
Metabolism
Definition
The chemical reactions that occur within cells. How organisms extract energy from nutrients and transform it to do work.
Term
Metastasize
Definition
When cancer cells spread rapidly through the body to the lymph nodes and vital organs.
Term
Mice
Definition
A popular test animal.
Term
Microglia
Definition
Cells in the central nervous system. Mobile macrophage-like immune cells.
Term
Midbrain
Definition
Part of the brainstem. Relays information between cerebellum and spinal cord. Controls reflex response to sudden stimuli.
Term
Middle age
Definition
The life stage between ages 40 and 60. A period of uncertainty, anxiety, and change. Questioning of achievements, goals, and values. Uncertainty in roles when children become adults.
Term
Middle Ages medicine
Definition
Illness was seen as God's punishment for misdeeds or from the presence of evil spirits. Scientific investigations of cadavers was prohibited. Treatments included self-punishment, abstinence, prayer, and hard work.
Term
Migrant defense system
Definition
Part of the local support and defense system.
Term
Miature swine
Definition
A test animal. A model for adult human diseases and aging. Newborn piglets are a good model for human infants. They can be cloned.
Term
Molecule
Definition
Cells are composed of molecules.
Term
Monism
Definition
Viewing the mind and body as one unit together.
Term
Morbidity
Definition
Illness rate.
Term
A naturally occurring physiological agonist. A natural pain killer. Can be consumed to give euphoria. Present in a runner's high, and in the opium poppy. Blocks GABA, a dopamine inhibitor.
Definition
Term
Mortality
Definition
Death rate.
Term
Motor functional areas
Definition
Areas of the cerebrum that control contraction of skeletal muscles. Includes primary motor area and premotor cortex in the frontal lobe.
Term
Motor neurons
Definition

aka Efferent neurons

Respond to information from sensory neurons, conducting information away from the brain and spinal cord to effectors.

Term
Mucous membranes
Definition
A type of membrane. Lines passageways that open to the exterior of the body: respiratory, digestive, reproductive, and urinary systems. Some, such as that of the intestines, is specialized for absorption. Some, such as the respiratory system, secrete mucous that traps bacteria and viruses.
Term
Multiple sclerosis
Definition
The myelin sheaths in the brain and spinal cord are destroyed. Damaged regions become hardened and interfere with transmission of nerve impulses, causing blocks and short-circuiting. The person is paralysed and/or loses sensation including vision.
Term
Muscle fibres
Definition
The cells of muscle tissue. Contract when stimulated.
Term
Muscle tissue
Definition
A tissue type. Provides body movement and the movement of substances through the body. The cells are called muscle fibres. Includes skeletal muscle, cardiac muscle, and smooth muscle.
Term
Muscular system
Definition
Moves body and maintains posture, internal transport of fluids, and generation of heat.
Term
Myasthenia gravis
Definition
An autoimmune disease where the body's defence mechanisms attack acetylcholine receptors at neuron-motor cell junctions. The person has reduced muscle strength. Repeated movements quickly become feeble.
Term
Myeline sheath
Definition
An outer layer surrounding axons outside of the brain and spinal cord. Many layers of twisted plasma membrane of Schwann cells. Greatly increses the rate of conduction of a nerve impulse; there is salutatory conduction. Prevent short-circuiting of nerve impulses. Play a role in mending damaged nerve axons.
Term
Myosin
Definition
A protein found in striations. Interacts with actin to produce muscle contractions.
Term
Nails
Definition
Part of the integumentary system. Modified skin cells hardened by keratin. Protect the fingertips and toes. Aid us in manipulating objects. Dead and lack sensory receptors. The tissue beneath a nail is so sensitive that we can detect pressures on the nail. Nails grow continuously.
Term
Natural Science and Engineering Research Council (NSERC)
Definition
A Canadian government funding organization for medical research.
Term
Natural selection
Definition
The process by which populations of organisms evolve. Individuals with more beneficial traits are more likely to pass their genes onto their offspring.
Term
Negative feedback mechanism
Definition
The mechanism by which homeostasis is maintained. When conditions stray outside of the acceptable range, they activate and return conditions back into range, at which point the mechanism ceases. Three components: receptors, control center, and effector.
Term
Nephritis
Definition
A leading cause of death in Canada. 1.6% of deaths.
Term
Nerve
Definition
A bundle of axons and/or dendrites covered with connective tissue.
Term
Nerve impulse
Definition
An electrochemical signal caused by potassium and sodium ions. Travels like a wave down an axon.
Term
Nerve tissue
Definition
A tissue type. Conducts nerve impulses from one part of the body to another. Includes the brain, spinal cord, and nerves. There are two types of cells: neurons and neuroglia.
Term
Nervous system
Definition
Regulates and integrates body functions via neurons. Has elements in the skin allowing us to sense temperature, tough, pressure, and pain. Provides immediate, quick homeostasis responses to changes in internal and external conditions. Consists of neurons and neuroglial cells. Capable of communicating long distances by transmitting chemical signals. Communication between neurons occurs over synapses between neurons and neurons, muscles, or glnds. Messengers are neurotransmitters. Includes the central and peripheral nervous systems.
Term
Neurocrine system
Definition
A hybrid between the nervous and endocrie system. Neurons release neurohormones into the blood. Intermediate response duration time and speed.
Term
Neuroglia
Definition

aka Glial cells

A type of cell in nerve tissue. Ten times more numerous than neurons. Support, insulate, and protect neurons. Provide neurons with nutrients from nearby blood cells. Increase the rate at which impulses are conducted from neuron to neuron. Can communicate with each other and with neurons.

Term
Neurohormone
Definition
A class of hormone. Released by neurosecretory cells in the neurocrine system. Includes vasopressin.
Term
Neuron
Definition

aka Nerve cell

A type of cell in the nervous system. Generates and conducts nerve impulses to other neurons, muscle cells, or glands. Secretes neurotransmitters from the axon. Have a wide diversity of size and shape. Has three parts: cell body, dendrites, and axon. Include sensory neurons, motor neurons, and interneurons. Built for one-way, speedy interactiosn with specific target cells. Diverge, converge, and form networks.

Term
Neurosecretory cells
Definition
An endocrine gland which releases neurohormones.
Term
Neurotransmitter
Definition
A type of chemical messenger. Secreted from neurons at the axon terminal. Diffuses across the synaptic cleft in synaptic signalling. Includes amines, peptides, and proteins. Includes acetylcholine, dopamine, and norepinephrine. After they have transmitted their signal they are cleared from the synaptic cleft by being deactivated by enzymes, or being pumped back into the synaptic knob.
Term
New biology
Definition
Began in 2008. How can fundamental understanding of living systems reduce uncertainty about the future of life on earth, improve human health and welfare, and lead to the wise stewardship of our planet?
Term
New physiology
Definition
Looks at elements within tissues, organs, and organ systems involved in control and communication of information. Biological network analysis.
Term
Nitrous oxide
Definition
A chemical messenger which does not fall into any chemical classification.
Term
Nodes of Ranvier
Definition
Gaps between myelin sheaths between Schwann cells. The nerve impulse has saltuatory conduction between these points.
Term
Non-intervention studies
Definition
A type of clinical trial. Subjects are not given medicinal treatment. Cannot be used to predict or prove cause and effect of a medicinal substance, just to predict associations and correlations. Includes epidemiolgical studies.
Term
Nootropics
Definition

aka Smart drugs

Natural health products and drugs used for cognitive enhancement in the elderly. 

Term
Norepinephrine
Definition

aka Noradrenaline

A catecholamine neurotransmitter. Synthesized from dopamine in vesicles, catalyzed by dopamine β-hydroxylase. Stimulates most organs. Acetylcholine has the opposite effect of norepinephrine. Controlls attention, arousal, sleeping/waking, learning, memory, pain, anxiety, and mood.

Term
Obsessive comulsive disorder (OCD)
Definition
A mental illness. In a PET scan, the brain is highly active even when at rest.
Term
Occipital lobe
Definition
A lobe of the cerebrum. Functions in visual association and vision.
Term
Occupational health
Definition
One of the seven dimensions of health. Satisfaction a person gets from their career or stage of career development, attaining and maintaining a satisfying balance between work and leisure.
Term
Oil glands
Definition

aka Sebaceous glands

Develop from epidermal cells. Found all over the body except for the palms of the hands and soles of the feet. Secrete sebum into the dermis. Produce more sebum during adolescence due to androgens in the blood.

Term
Olfactory bulb
Definition
Part of the limbic system. Transmits information about odours to the limbic system. Why we often have emotional responses to smells, and smells can bring up specific memories.
Term
One Health
Definition

aka One World

aka One Medicine

A component of collective medicine. Older and more prominent than EcoHealth. An animal-human health continuum focusing on zoonosis.

Term
Open head injury
Definition
A traumatic brain injury where the skull is broken, damaging the brain underneath.
Term
Opposable thumb
Definition
One of the characteristics that humans share with other primates. A thumb that can touch the tips of the other four fingers.
Term
Oral acne treatment
Definition
Acne treatment that is taken by mouth. Inhibits bacterial growth in the follicle, or poisons oil glands, causing them to shrink permanently and produce less sebum.
Term
Organ
Definition
A structure with two or more different tissues working together to perform a specific function. Usually belong to an organ system.
Term
Organ system
Definition
A group of organisms with a common function. The twelve organ systems in humans are: integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, respiratory, digestive, urinary, reproductive, and energy distribution.
Term
Organelle
Definition
Complex compartments found in eukaryotic cells.
Term
Organizational support
Definition
A support which may lead to a health promotion. Programs and services that encourage participation in health.
Term
Osteoporosis
Definition
Biomarkers include reduced height and bone density. DEXA scores between -1.0 T and -2.8 T. The most effective way to avoid low bond density is to reach peak bone density at age 20 - 30 by getting sufficient calcium and vitamin D, doing weight bearing physical activity, maintaining stable body mass, and getting plenty of sleep.
Term
Overgeneralization
Definition
When a study explores issues for one sex or age group and generalizes the functions, assuming it would have identical results with the other sex or other age groups.
Term
P4 medicine
Definition
Personalized, Predictive, Preventative, and Participatory.
Term
Pancreas
Definition
An endocrine gland which secretes insulin.
Term
Paracrine
Definition
A type of chemical messenger. Secreted and difuses a short distnce to a target cell which is nearby. Includes amines, peptides, proteins, and eicosanoids. Includes growth factors, clotting factors, histamine, and autocrines.
Term
Parasympathetic nervous system
Definition
Part of the autonomic nervous system. Adjusts bodily functions so that energy is conserved during non-stressful times.
Term
Parietal lobe
Definition
A lobe of the cerebrum. Includes the primary somatosensory area, the gustatory (taste) area, and areas used during reading.
Term
Parkinson's disease
Definition

Dopamin-producing neruons in the brain's movement centre die. The person moves more slowly, with a shuffling gait and hunched posture. May have involuntary muscle contractions such as shaking of the hands and head. May have muscle rigidity in the middle of movements. Treatments include amino acids that can be converted into dopamine.

Michael J. Fox and Muhammad Ali have Parkinson's disease.

Term
Participatory
Definition
The fourth P in P4 medicine. The patient must participate and engage in their own health. This is the biggest challenge of P4 medicine.
Term
Pathology
Definition
The study of physiology when it has gone wrong.
Term
Peptides
Definition
A chemical classification of chemical messengers. Peptides longer than 50 amino acids are classified as proteins. Most messengers are peptides or proteins. Lipophobic. Synthesized from propeptides in the Golgi apparatus and packaged into secretory vesicles for release by exocytosis.
Term
Pericardial cavity
Definition
A division of the thoracic cavity. Contains the heart.
Term
Pericyte
Definition
One of the cells in the blood-brain barrier. Between the endothelial cell and the astrocyte foot.
Term
Periodontitis
Definition
A disease of the gums which may require teeth to be pulled. Caused by lifestyle; people who floss are much less likely to get periodontitis.
Term
Peripheral nervous system (PNS)
Definition
A part of the nervous system. Includs the somatic and autonomic nervous system. Branches off of the central nervous system. Includes the somatic nervous system and autonomic nervous system.
Term
Personalized
Definition
The first P of P4 medicine. Directed towards the individuality of the patient. Genetic, multi-modal, behavioural, and psychological analysis.
Term
PET scan
Definition
Allows us to watch what parts of the brain are active during different activities and thoughts.
Term
Phenoxybenzamine
Definition
A drug that is in an antagonist for α adrenergic receptors. Causes a reduction in the effects of epinephrine and norepinephrine. Blood pressure decreases.
Term
Phenylephrine
Definition
A drug that is an agonist for α adrenergic receptors. Causes the same effects as epinephrine and norepinephrine.
Term
Phenylethanolamine N-methyl transferase (PNMT)
Definition
Catalyzes the conversion of norepinephrine into epinephrine in vesicles.
Term
Phinease P. Gage
Definition

1823 - 1860

A man who survived for twelve years after being impaled through the skull with a railroad spike. Most of his frontal lobe was destroyed. His personality was changed after the accident; he went from being a nice guy to being disagreeable.

Term
Phlegm
Definition
A humor in the humoral theory. Associated with winter. Cold and wet. Associated with a phlegmatic, calm temperament.
Term
Phosphatidylinositol-4,5-biphosphate (PIP2)
Definition
Undergoes a reaction catalyzed by phospholipase C in the phosphatidylinositol system that liberates DAG and IP3.
Term
Phosphatidylinositol system
Definition
PIP2 liberates DAG and IP3, catalyzed by phospholipase C, stimulating the release of calcium.
Term
Phospholipase A2
Definition
Catalyzes the release of arachidonic acid from the membrane for the synthesis of eicosanoids.
Term
Phospholipase C
Definition
Catalyzes the conversion of PIP2 into DAG and IP3. G protein activated.
Term
Phosphoprotein phosphatase
Definition
Dephosphorylates proteins that protein kinase A has phosphorylated.
Term
Physical health
Definition
One of the seven dimensions of health. Body size and shape, sensory acuity, susceptibility to disease and disorders, body function, recuperativ ability, ability to perform activities of daily living.
Term
Physiome
Definition
Every aspect of our bodies.
Term
Phytoestrogen
Definition
An antagonist of estrogen.
Term
Pia mater
Definition
The lower layer of the meninges. Molded into the crevices of the brain. Attached to the arachnoid.
Term
Piloerection
Definition

aka Goosebumps

Caused by contraction of the arrector pili muscles when temperatures are too low. Hairs stand on end, trapping an insulating layer of air near to the body. Less effective in humans than in harrier animals.

Term
Placebo
Definition
A treatment given to the control group of a clinical trial that is an innocuous, non-drug substance made to look like the drug being tested. It is important the participant does not know what group they are in because it could affect how they respond to the test.
Term
Placebo effect
Definition
When people who take a placebo experience an improvement in health. Because the placebo lacks any medicinal properties, it can be assumed that the improvement is due to psychological effects only.
Term
Plants
Definition
A kingdom of Eukarya.
Term
Plasma
Definition
The matrix of blood. A fluid. Many of the substances blood transports is dissolved in plasma. Contains formed elements.
Term
Platelets
Definition
A formed element in blood. Helps with blood clotting.
Term
Pleural cavity
Definition
A division of the thoracic cavity. Contains the lungs.
Term
Pons
Definition
Part of the midbrain. A bridge between higher and lower brain centres. Connects the spinal cord and cerebellum to the cerebrum, thalamus, an hypothalamus.
Term
Population
Definition
A group of individuals of the same species. Comprises a community.
Term
Postprandial
Definition
Following a meal.
Term
Postsynaptic neuron
Definition
The neuron which recieves neurotransmitters in synaptic signalling.
Term
Pre-operational
Definition
The life stage between ages 2 and 7. Symbolic though develops, followed by simple logic and language. Child is egocentric.
Term
Predictive
Definition
The second P in P4 medicine. New technologies allow us to predict more accurately the risks for diseases and accelerated aging.
Term
Prefrontal cortex
Definition
A region of the frontal lobe of the cerebrum. An association functional area. The most anterior part of the frontal lobe. Predicts consequences of possible responses, and decides which response is best. Gives us ability to reason, plan, and have abstract thoughts. Plays a role in personality.
Term
Premotor cortex
Definition
A region of the frontal lobe of the cerebrum. A motor functional area. Co-ordinates learned motor skills such as typein or playing musical instruments.
Term
Prepropeptide
Definition
Synthesized into the lumen of the endoplasmic reticulum from translating mRNA. Proteolytic enzymes cleave off amino acids, turning them into propeptides.
Term
Presynaptic neuron
Definition
The neuron which releases neurotransmitters from its synaptic knob to the postsynaptic cell in synaptic signalling.
Term
Prevalence
Definition
The number of established cases of a disease in a population at any one time.
Term
Preventative
Definition
The third P in P4 medicine. Avoiding or delaying the onset of disease and accelerated aging and potentially other forms of suboptimal health.
Term
Preventative medicine
Definition
A component of medicine. Physicians give patients interventions, and attempt to asses the risks of diseases and disorders.
Term
Primary literature
Definition
Search engines include PubMed/Medline. It can be hard to find information on how primary literature is translated into current medical and healthcare practices.
Term
Primary motor area
Definition
A region of the frontal lobe of the cerebrum. A motor functional area. Forms a band anterior to the primary somatosensory area. Parts of the body with finer control have larger surface area representation. Body part regions line up roughly with their correlating regions of the primary somatosensory area.
Term
Primary prevention
Definition
Actions that can prevent health problems before they occur. Example: immunization, not smoking, safe sex, eating well, and regular exercise.
Term
Primary somatosensory area
Definition
A region of the parietal lobe of the cerebrum. A sensory functional area. Forms a band posterior to hte primary motor area. More sensitive parts of the body have larger surface area representation. Body part regions line up roughly with their correlating regions of the primary motor area.
Term
Primates
Definition
A group within mammals. Includes lemurs, monkeys, apes, and humans. We share many features with other primates including teeth and skeletal similarities, and opposable thumbs. A test animal. Baboons are studies in the wild. Rhesus monkeys are the main laboratory test primate. No primate research is done in Canada.
Term
Prokaryotes
Definition
Includes the domains bacteria and archaea. Single-celled organisms that lack a nucleus and other internal compartments.
Term
Propeptide
Definition
Synthesized from prepropeptides in the endoplasmic reticulum by cleaving amino acids off, catalyzed by proteolytic enzymes.
Term
Prostacyclin
Definition
An eicosanoid synthesized in the cyclooxygenase pathway. Involved in inflammation reponses.
Term
Prostglandin
Definition
An eicosanoid synthesized int he cyclooxygenase pathway. Involved in blood clotting.
Term
Protein
Definition
A chemical classification of chemical messengers. Proteins are greater than 50 amino acids long. Most chemical messengers are peptides or proteins. Lipophobic.
Term
Protein fibres
Definition
A component of matrix in connective tissues. There are three types: collagen, elastic, and reticular fibres. Produced by fibroblasts.
Term
Protein kinase A
Definition
A cAMP-dependent protein kinase. Activated by cAMP. Transfers a phosphate group from ATP to a protein. This can be reversed by phosphoprotein phosphatases.
Term
Protein kinase C
Definition
Activated by DAG. Catalyzes the phosphorylateion of a protein.
Term
Protein kinase G
Definition
cGMP-dependent protein kinase. Activated by cGMP.
Term
Proteolytic enzymes
Definition
Catalyze cleaving amino acids off of prepropeptides, turning them into propeptides in the endoplasmic retiulum.
Term
Protists
Definition
A kingdom of Eukarya.
Term
Psoraisis
Definition
A non-contagious disorder where skin cells reproduce at an elevated rate and dead cells clump up making scaly, itchy, and painful red lesions on the skin. The body is fooled into thinking something is wrong so the basal cells reproduce excessively. Symptoms include fear, helplessness, shame, rage, guilt, stigma, anxiety, worry, depression, fatigue, sleeplessness, and sexual dysfunction. Increased risk for psoriasis include genetic, geographical, and certain medications.
Term
Puberty
Definition
A period of physical and psychosocial change that influences self-perception. At age 11 - 13, individuals prepare for independence and peers take on more credence than parents.
Term
PubMed
Definition
A primary research literature search engine sponsored by the US National Institute of Health and Google Scholar. Presents the most recently published results first. Can be difficult to see how results are translated into current medical and healthcare practices.
Term
Pustule
Definition

aka Pimple

When acne is infected by bacteria.

Term
Rats
Definition
A test animal. Inbred strains. Voluntary exercise. Can be used research learning. Not a good model for human infants.
Term
Receptor (chemical messengers)
Definition
Binds to specific chemical messengers, causing signal transduction reactions. Binding is brief and reversible. Receptors and messengers can have differing affinity.
Term
Receptor (homeostasis)
Definition
A component of a negative feedback mechanism. Detects changes in the internal or external environment. If a change is detected, it sends a message to the control centre.
Term
Red blood cells
Definition
A type of formed element in blood. Transports oxygen to cells and brings carbon dioxide away.
Term
Red marrow
Definition
The portion of bone where blood cells are produced.
Term
Reductionism
Definition
A perspective in biology. Focused on how each part of a system works on its own.
Term
Reflex
Definition
An automated response to stimulus that is prewired into a reflex arc.
Term
Reflex arc
Definition
A prewired circuit of neurons in the gray matter of the spinal cord. Produces a reflex. Includes a sensory neuron, at least one interneuron, a motor neuron, and an effector.
Term
Refractory period
Definition
The minimum period between nerve impulses. Increases with the strength of the stimulus.
Term
Rene Descartes
Definition

1596 - 1650

Proposed that the mind and body were separate entities. Had limited understanding of how the two interacted.

Term
Repolarization
Definition
In action potential, the negative charge is restored in the cell by potassium ions leaving the axon.
Term
Reproduction
Definition
Some organisms copy themselves exactly when reproducing. Others combine their genetic material with another individual to reproduce.
Term
Reproductive system
Definition
Produces and secretes hormones. Produces and releases egg and sperm cells. In females, it houses the embryo/fetus.
Term
Research money
Definition
Research can be very expensive. Costs include personnel, equipment and supplies, compensation money for research subjects, and publication costs. Money is obtained from private donors, philanthropic organizations, small grants from non-profit organizations, and advocacy groups, but most of the money comes from the government.
Term
Resident defense system
Definition
Part of the local support and defense system.
Term
Respiratory system
Definition
Exchanges respiratory gases with the environment.
Term
Respiratory diseases
Definition
A leading cause of death in Canada. 4.6% of deaths.
Term
Resting potential
Definition
The difference of charge between the inside and outside of a neuron axon at rest. More potassium ions outside and more sodium ions inside. The inside is more negative than the outside. Has a voltage about 5% than of an AA battery. Allows the neuron to respond quickly to stimuli.
Term
Reticular activating system (RAS)
Definition
A network of neurons that runs through the medulla oblongata to the cerebral cortex. Acts as a filter for sensory input, filtering out repetitive, familiar stimuli, and allowing important stimuli to be processed. Sleep is when the RAS is inhibited. Consciousness depends on the RAS.
Term
Reticular fibres
Definition
A type of protein fibre found in connective tissue matrix. Thin strands of extensively branched collagen. Forms a network that supports soft tissues such as the liver and spleen.
Term
Rhesus monkey
Definition
The main laboratory primate model species.
Term
Robot
Definition
A type of simulated experimental system.
Term
Root
Definition
A part of a hair. The portion which extends below the surface of the skin into the dermis or hypodermis. It is embedded in the follicle.
Term
Saltatory conduction
Definition
The conduction of a nerve impulse, jumping between nodes of Ranvier. Much faster than if there were no myelin sheath.
Term
Saturation
Definition
When all receptors have messenger bound to them.
Term
Scale-free network map
Definition
A network map with no anatomical grounding.
Term
Scaled network map
Definition
A network map with physical grounding base of the physical dimensions of the network. It has anatomical reality.
Term
Schizophrenia
Definition
A mental illness. When the person says they are hallucinating voices, the parts of the brain that light up when listening to real-life words light up in a PET scan.
Term
Schwann cells
Definition

aka Oligodendrocytes

Cells with plasma membranes that are coiled around axons, forming myelin sheaths. One Schwann cell covers around 1 mm of the axon. Between Schwann cells are nodes of Ranvier.

Term
Science
Definition
The systematic approach humans use to answer questions and acquire knowledge through carefully documented investigation and experimentation. Uses scientific method.
Term
Scientific method
Definition
Making careful observations, developing a hypothesis, making a prediction and testing it, then drawing a conclusion.
Term
Sebum
Definition
The substance secreted by oil glands in the skin. Contains fat, cholesterol, proteins, and salts. Lubricates the hair and skin and inhibits growth of certain bacteria. If blocked, sebum may accumulate in the duct of the oil gland, leading to acne.
Term
Second degree burn
Definition
A burn which reaches the upper layers of the dermis.
Term
Second messenger
Definition
Release is triggered by the first messenger, catalyzed by amplifier enzymes in signal transduction.
Term
Secondary prevention
Definition
Actions that reduce symptoms or halt or slow the progression of disease early on in its development. Example: changing died fter a blood-cholesterol or blood-glucose test.
Term
Self-concept
Definition
The conscious thoughts and beliefs about oneself that makes us feel distinct from others. Stable through aging.
Term
Sensorimotor
Definition
The stage of life between birth and age 2. Infnt understands the world through sensations and movement. Lacks symbolic thought. Goes from reflexive to voluntary motion.
Term
Sensory functional areas
Definition
Areas of the cerebrum that give awareness of sensations. Receptors in the body send information to these areas. Includes the primary somatosensory area in the parietal lobe.
Term
Sensory neurons
Definition

aka Afferent neurons

Conduct information inwards towards the brain and spinal cord. Extend from sensory receptors specialized for gathering information about conditions within and around the body.

Term
Serotonin
Definition
An amine chemical messenger derived from tryptophan. Produces a good feeling. Controls locomotion, pain, sleeping/waking cycles, and emotion.
Term
Serous membrane
Definition
A type of membrane. Lines the ventral body cavity and the organs within it. Secretes a fluid which lubricates the organs.
Term
Seven dimensions of health
Definition
Physical, mental, social, emotional, environmental, occupational, and spiritual health. The balance strived for in integrative medicine.
Term
Sex differences
Definition
Some diseases are more common in one sex than the other. Some diseases can have different symptons in one sex than in the other.
Term
Sex insensitivity
Definition
Overlooking sex as an important variable in studies. Excluding a sex from a study, or analyzing data from both sexes together without first checking to see if there are any significant differences between the data.
Term
Shaft
Definition
A part of a hair. The portion which projects above the surace of the skin. It is connected to the root.
Term
Short-term memory
Definition
Memories held for a few seconds or minutes in the limbic system.
Term
Sigmund Freud
Definition
In the 1920s and 30s he postulated an "unconscious mind". Identified unconscious conflicts using hypnosis and free association. The conflicts were attributed as the cause of illnesses to whcih a physical explanation could not be found, such as hysterical paralysis. Lead to psychosomatic medicine.
Term
Signal amplification
Definition
In signal transduction the first messenger triggers release of a second messenger, which triggers the relase of a third messenger, causing a cascade. Each step multiplies the signal.
Term
Signal transduction
Definition
The reaction a target cell has to a chemical messenger. The higher the concentration of messenger, the more receptors available, and the stronger the affinity between messenger and receptor, the stronger the reaction.
Term
Simple
Definition
Epithelial tissue that is one single layer of cells.
Term
Simple columnar
Definition
Columnar epithelial tissue in one layer. Found in the gut and respiratory tract. Absorbs and secretes.
Term
Simple cuboidal
Definition
Cuboidal epithelial tissue in one layer. Found in the linings of the kidney tubules and in the ducts and secretory parts of glands. Absorbs and secretes.
Term
Simple squamous
Definition
Squamous epithelial tissue in one layer. Found in the lining of the lungs, alveoli, heart, and blood vessels. Allows for exchange of nutrients, gasses, and wastes by diffusion.
Term
Skeletal muscle
Definition

aka Voluntary muscle

A type of muscle tissue. Most are attached to the skeleton by tendons. When they contract, the body moves. Long cylindrical striated cells with many nuclei. Produce voluntary movement.

Term
Skeletal system
Definition
Attaches to muscles, protects organs, stores calcium and phosphorus, and produces blood cells.
Term
Skeleton
Definition
A structure of bone, cartilage, and other joint-forming substances that gives the body structure.
Term
Skin
Definition
A part of the integumentary system. Protects the body contents from bacteria, harmful particles, UV radiation, and physical and chemical injury. Has nervous system structures for detecting temperature, touch, pressure, and pain. Includes macrophages. Contains keratin. Produces vitamin D. Less than 5 mm thick. One twelfth of the body's weight. Surface area of 1.5 - 2.0 meters squared. Has two layers: the epidermis and dermis.
Term
Skin cancer
Definition
Caused by UV radiation damaging genetic material in the skin cells, forming a tumor. Rates of skin cancer will increase if the ozone layer in the atmosphere becomes thinnger. There are three types of skin cancer: basal cell carcinoma, squamous cell carcinoma, and melanoma. Treated by excision, radiation, laser surgery, cryosurgery (freezing), or electrodessication (electric current). The best way to avoid skin cancer is to not go tanning, and to wear hats, long sleeves, sunglasses, and sunscreen in the sun.
Term
Skin colour
Definition
Determined by blood flow and the quantity and distribution of melanin pigment. Melanin pigment is a genetic factor. Well-oxygenated skin is pinker in colour, but this effect is more noticeable in light-coloured skin. Embarrassment can cause blushing of the cheeks from a sudden blood rush to the face. Fright and cold can reduce blood flow, making skin paler. Not enough sleep leads to less oxygenated skin beneath theeyes, making dark patches.
Term
Skull
Definition
A bone that protects the brain.
Term
Sleep
Definition
A complex process controlled by the brain. The RAS is inhibited. Co-ordinated with natural and artificial light. Too little, to much, or irregular sleep can be risk factors for the CCN. Disrupted sleep increases cardiovascular mortality, cancer risk, impairs learning and memory, and icreases accidences. Balanced, regular sleep increases healthspan.
Term
Sleeper-hold
Definition
A fight move that involves cutting off blood supply to the brain. Renders the victim unconscious after 5 - 10 seconds.
Term
Slow channels
Definition
A channel-linked receptor where the first messenger binds to a G protein, causing the channel to open or close. Reaction is a few minutes.
Term
Smooth muscle
Definition
A type of muscle tissue. Found in the walls of hollow internal organs including the digestive system, blood vessels, airways, and tubules of the urinary system. Propels substances through internal passageways by controlling the diameter of tubes. Non-striated, one-nucleus cells tapered at each end. Arranged in sheets. Produces involuntary contractions.
Term
Social health
Definition
One of the seven dimensions of health. Satisfying interpersonal relationships, interaction with others, adaptation to social situations, communication skills.
Term
Sodium-potassium pumps
Definition
An ion channel in neuron axons that slowly transport sodium ions out and potasssium ions in, using ATP, maintaining the resting potential of the axon.
Term
Somatic nervous system
Definition
Part of the peripheral nervous system. Nerves that carry information to and from the central nervous system. Results in sensation and voluntary movement.
Term
Specialized connective tissue
Definition
A type of connective tissue. Includes cartilage, bone, and blood.
Term
Spinal cavity
Definition
A division of the dorsal body cavity. Contains the spinal cord.
Term
Spinal cord
Definition
Part of the central nervous system. Found in the spinal cavity. A tube of nervous tissue that is continuous with the medula oblangata and extends 45 cm below the last rib. The diameter of a pinky finger. Protected by the vertebral column. Pairs of nerves exit the spinal column between each vertebrae. Has an outer layer of white matter that includes ascending and descending tracts that transmit messages to and from the brain. Has an inner layer of gray matter that has reflex arcs.
Term
Spirit
Definition
The deepest and innermost part of you that understands the world and your role in it.
Term
Spiritual health
Definition
One of the seven dimensions of health. The ability to draw strength from the spirit, know who you are, and your specific purpose. May involve a specified religion or belief system, or from personal relationships with others or with nature.
Term
Squamous
Definition
A shape of epithelial tissue. Flattened and scale-like cells. Includes simple and stratified.
Term
Squamous cell carcinoma
Definition
A type of skin cancer. The second most common type of skin cancer after basal cell carcinoma. Found in the newly formed skin cells of the epidermis.
Term
Standard error
Definition
The degree of certainty of the results of a controlled experiment.
Term
Statistical significance
Definition
A measure of the possibility that the results of a controlled experiment were due to chance. If less than 0.05, the results can be considered significant.
Term
Steroid
Definition
A chemical classification of chemical messengers. Derived from cholesterol in a series of enzyme-catalyzed reactions in the smooth endoplasmic reticulum. Act like hormones. Lipophilic. Has the basic ring structure of cholesterol. There is no storage method because it can diffuse through membrane; it is synthesized on demand and released immediately.
Term
Stimulatory G proteins
Definition
G proteins that activate enzymes.
Term
Stratified
Definition
Epithelial tissue that is in multiple layers of cells. Often surves for protection.
Term
Stratified columnar
Definition
Columnar epithelial tissue in multiple layers. Rare. Found in the urethra and in the junction between esophagus and stomach. Provides protection and secretion.
Term
Stratified cuboidal
Definition
Cuboidal epithelial tissue in multiple layers. Found in two layers in the mammary, sweat, and salivary glands. Provides protection.
Term
Stratified squamous
Definition
Squamous epithelial tissue in multiple layers. Found on the skin, lining of the mouth, esophagus, and vagina. Provides protection from abrasion, infection, and drying out.
Term
Stretch marks
Definition
Created when the elasticity of the skin is exceeded, such as during pregnancy or rapid weight gain.
Term
Striations
Definition
Visible dark bands that can be seen on the muscle fibres of skeletal and cardiac muscle tissue. Arrangements of contractile proteins actin and myosin, which interact to cause muscle contraction.
Term
Suicide
Definition
A leading cause of death in Canada. 1.6% of deaths.
Term
Summation
Definition
The sum of excitatory and inhibitory synapses. One neuron can have up to 10,000 synapses occuring at the same time. These interactions add up to an overall reaction. All the synapses in the body allow us to have thoughts, feelings, and interact with the world around us.
Term
Sunburn
Definition
UV radiation damage to the skin. Blood vessels dilate, causing reddening. Surface skil cells ar damaged and may peel off.
Term
Sunscreen
Definition
Should be worn to reduce chances of skin cancer, even when it is overcast. Should have an SPF of at least 15.
Term
Supertaster
Definition
Someone who has an elevated sensitivity to taste, especially bitterness. 25% of North Americans are supertasters. Less likely to consume alcohol or cigretttes. Increased preference for sweetness. More likely to avoid vegetables. Higher risk for colon cancer.
Term
Suprachiasmatic nucleus
Definition
The part of the hypothalamus that times and co-ordinates body rhythms. Circadian rhythms are based on light signals from the retina.
Term
Sweat
Definition
The product of sweat glands. Mostly water, with some salts, lactic acids, vitamin C, and metabolic wastes including urea. Regulates body temperature by evaporating off of the skin, reducing temperature.
Term
Sweat glands
Definition
Glands in the skin. Produce sweat almost constantly, but during times of strenuous exercise or high temperatures, the hypothalamus sends a signal to the sweat glands to increase sweat production.
Term
Sympathetic nervous system
Definition
Part of the autonomic nervous system. Takes charge during stressful or emergency conditions.
Term
Synapse
Definition
The joint between the presynaptic and postsynaptic neurons in synaptic signalling. Includes the synaptic knob and synaptic cleft.
Term
Synaptic cleft
Definition
The space between the presynaptic and postsynaptic neurons.
Term
Synaptic knob
Definition
A bulblike swelling at the end of the axon of the presynaptic neuron. Has synaptic vesicles.
Term
Synaptic signalling
Definition
The transfer of neurotransmitters between presynaptic and postsynaptic neruons. Directed to specific cells. A nerve impulse reaches the synaptic knob and calcium ions move into the knob, causing exocytosis of synaptic vesicles, releasing neurotransmitters into the synaptic clef, where they bind with receptors on the postsynaptic neuron, triggering a nerve impulse.
Term
Synaptic vesicle
Definition
Vesicles in the synaptic knob containing neurotransimtters. Fuse with the plasma membrane in synaptic signalling, releasing neurotransmitter.
Term
Synovial membrane
Definition
A type of membrane. Lines the cavities of freely movable joints, such as the knee. Secretes a fluid which lubricates the joint, easing movement.
Term
Systems biology
Definition
A new era in biology that incorporates the defining ideas of logic units and information flow in biological systems. Brings together issues in health and biology.
Term
Tamoxifen
Definition
An antagonist of estrogen. Used to treat breast cancer. Interfers with the binding of endogenous estrogen to estrogen receptors in cancer cells.
Term

 

Tanning

Definition
When melanocytes are exposed to UV radiation, they increase the production of melanin as a protective response.
Term
Target cell
Definition
The cells which are effected by chemical messengers. Have receptors that bind to chemical messengers, causing signal transduction.
Term
Taste
Definition
There are six tastes: sweet, salty, sour, bitter, umami, and fat.
Term
Tattoos
Definition
Created by injecting ink into the dermis, which does not shed. The dermis has nerves, so getting a tattoo is painful. In the past, the only way to remove a tattoo ws to shave off the dermal layer from the skin. But new lasers can now be used to destroy tattoo ink pigments.
Term
Temporal lobe
Definition
A lobe of the cerebrum. Functions in hearing, olfaction, language understanding, and auditory association.
Term
Tendon
Definition
A type of dense connective tissue proper. Connects bones to muscles.
Term
Tertiary prevention
Definition
Treatment and rehabilitation efforts for the effects of a disease after it has developed. Most government dollars go into this form of prevention. Example: chemotherapy, coronary bypass surgery. More costly, more dangerous, and less effective than primary and secondary prevention.
Term
Testosterone
Definition
A lipophilic sex hormone.
Term
Tetrahydrocannabinol (THC)
Definition
A naturally occuring physiologicl agonist. Found in marijuana. Interacts with cannabinoid receptors in the body.
Term
Thalamus
Definition
A part of the brain. Processes all sensory information except oflaction (smell). Sorts information of sensory experience, motor activity, and memory, and relays it. Determines if a sensation seems pleasant or unpleasant.
Term
Theory
Definition
A series of confirmed and repeated hypothesis fitting together to form a well-supported and wide-ranging explanation for some aspect of the universe. Cannot be proven in one experiment.
Term
Therapeutic medicine
Definition
A component of medicine. Physicians give patients treatments and attempt to diagnose the presense of diseases and disorders.
Term
Third degree burn
Definition
A burn which reaches all the way through the skin to the tissues below.
Term
Thoracic cavity
Definition
Chest cavity. A division of the ventral body cavity. Divided into pleural and pericardial cavities.
Term
Thromboxane
Definition
An eicosanoid synthesized in the cyclooxygenase pathway. Involved in blood clotting.
Term
Thyroid hormones
Definition
An amine chemical messenger derived from tyrosine. Lipophilic. Synthesized in the cytosol by enzyme-catalyzed reactions.
Term
Tight junction
Definition
A cell junction that attaches cells so well that they form a leak-proof seal. Prevents exchange between attached cells. Found in epithelial tissue lining of the urinary tract and the intestines, preventing digestive juices from passing through the epithelium.
Term
Tissue
Definition
Groups of similar cells that work together to perform a specific function. There are four types: epithelial, connective, muscle, and nerve. Tissues form organs.
Term
Tissue fluid
Definition
Brings nutrients from the dermis to the epidermis. This is the fluid that fills blisters and burns.
Term
Topical acne treatment
Definition
Acne treatment applied to the skin. Must be used for several weeks before improvements are noticed.
Term
Traditional physiology
Definition
Looks at the structure and function of tissues, organs, and organ systems.
Term
Transdermal drug administration
Definition
The administration of certain lipid-soluble drugs through a patch placed on the skin. The drug diffuses into the underlying connective tissues and is absorbed into the blood. Used when the drug must be administered continuously, such as birth control, treatment of menopausal symptoms, nicotine, and anti-emetics.
Term
Traumatic brain injury (TBI)
Definition
Brain injury caused by external forces. Includes open and closed brain injury.
Term
Trephination
Definition
An ancient practice of making a small hole in the skull for evil spirits to leave a sick person.
Term
Tunnelling nanotubes
Definition
A form of direct intercellular communication. Long tubes form between cells, longer and wider than gap junctions, through which substances may pass.
Term
Tyrosine
Definition
The precursor to catacholamines. Coverted into dopamine with the enzymes tyrosine β-hydroxylase and dopa decarboxylase in the cytosol.
Term
Tyrosine β-hydroxylase
Definition
One of the enzymes that catalyzes the conversion of tyrosine into dopamine in the cytosol. The other is dopa decarboxylase.
Term
Tyrosine kinase
Definition
An enzyme-linked receptor that catalyzes the addition of a phosphate group to side chains of amino acids.
Term
Ultradian
Definition
A biological rhythm with a period less than one day. Includes eating patterns.
Term
Uncertainty
Definition
Everything in biology has uncertainty. There is an element of chance in everything.
Term
Uniqueness
Definition
A biological concept of heath. Each human can be considered a unique biological system.
Term
Up-regulation
Definition
The cell increases the number of receptors. Occurs when exposed to lower levels of messenger for extended periods. Cell becomes more receptive to messenger.
Term
Urinary system
Definition
Maintains constant internal environment through excretion of nitrogenous waste.
Term
Variable
Definition
The factor that differs betwen control and experimental groups in a controlled experiment.
Term
Vasopressin
Definition

aka Antidiuretic hormone (ADH)

A neurohormone produced by neuroseretory cells in the hypothalamus. Target cells are in the kidneys, affecting the volume of urine secreted.

Term
Ventral body cavity
Definition
A main body cavity near the front of the body. Surrounded by serous membrane. Divided into the thoracic and abdominal cavities, which are separated by the diaphragm.
Term
Ventricles
Definition
Internal cavities of the brain. Lined wth ependymal cells which secrete cerebrospinal fluid. Filled with cerebrospinal fluid.
Term
Vertebrate
Definition
A subdivision of the animal kingdom. Animals with a nerve cord protected by a backbone. Humans belong to this group.
Term
Vitamin D
Definition
A vitamin produced from modified cholesterol molecules in the skin by UV radiation. It is then transported to the liver and kidneys where it is chemically modified to stimulate uptake of calcium and phosphorus in the digestive system.
Term
Vitiligo
Definition
A condition where melanocytes disappear partially or completely from certain regions of the skin, leavng light-coloured patches.
Term
Wax glands
Definition
Modified sweat glands found in the external ear canal. Produce wax that protects the ear by trapping small particles.
Term
Wellesley effect
Definition
When femle mammals (including humans) are living in close quarters, their menstrual cycles sinc up to the socially dominant female's, except if they are in a close relationship with a male mammal.
Term
Wellness
Definition
Similar to health. A dynamic, ever-changing process in which a person attempts to reach their fullest health potential.
Term
White blood cells
Definition
A formed element in blood. Fight infections.
Term
White matter
Definition
Myelinated axons beneath the cerebral cortex in the cerebrum. Allow regions of the brain to communicate with each other.
Term
Whitehead
Definition
A type of acne. Caused when the sebum blocking the pore is not mixed with melanin.
Term
WHO definition of health
Definition
A state of complete physical, mental, and social well-being. Not merely the absense of disease or infirmity.
Term
Wrinkles
Definition
As a person ages, the number of collagen fibres in the skin decrease and elastic fibres stiffen and thicken. This reduces the elasticity of the skin. Moisture and fat content of the hypodermis decreases. These changes cause wrinkles. May be treated with botox.
Term
Yang
Definition
Negative energy. Associated with the female gender.
Term
Yellow bile
Definition
A humor in the humoral theory. Associated with the summer. Hot and dry. Associated with a choleric angry temperament.
Term
Yellow marrow
Definition
The portion of bone where lipids are stored.
Term
Yin
Definition
Positive energy. Associated with the male gender.
Supporting users have an ad free experience!