Shared Flashcard Set

Details

Physiology Test 1
Chapters 7 and 8
193
Physiology
Undergraduate 3
02/06/2007

Additional Physiology Flashcards

 


 

Cards

Term
Physiology
Definition
Study of how the body works to maintain life
Term
Pathophysiology
Definition
How Physiological processes are altered in disease or injury
Term
Comparative Physiology
Definition
Compares similar organisms and the physiology of their bodies
Term
Stratus
Definition
Father of Physiology *First to apply phycical laws to our understanding of the functionf of the human body.
Term
Galen
Definition
physician *authority until the Renaissance *applied basic experimental methods to experiment
Term
William Harvey
Definition
Began the era of modern physiology *first to demonstrate the role of the heart and its pumping mechanisms
Term
Claude Bernard
Definition
Father of modern Physiology
Term
Walter Cannon
Definition
Wrote The Wisdom of the Body *Used the word homeostasis
Term
Homeostasis
Definition
Maintenance of fairly constant internal conditions *Maintained by negative feedback loops
Term
Nervous System
Definition
Divided into CNS and PNS
Term
Central Nervous System (CNS)
Definition
Brain and spinal cord
Term
Peripheral Nervous System (PNS)
Definition
Cranial and spinal nerves (all the other nerves in the body) *Derived from 31 pairs of cranial nerves under the brain or from the spinal nerves
Term
Cells of the Nervous System
Definition
Neurons and Supporting cells
Term
Neurons
Definition
functional units of NS
Term
Supporting cells (glial cells)
Definition
Help maintain homeostasis *Five times more common than neurons
Term
Soma, Dendrites, Axon
Definition
Parts of a Neuron
Term
Multipolar, Bipolar, Pseudopolar
Definition
Types of neurons based on structure
Term
Soma
Definition
Center of the cell, contains the nucleus, contains nissl bodies (ribosomes)
Term
Dendrite
Definition
Extensions of the cytoplasm, trasmit electrical signals towards the soma, shorter than axons, receptive ends, contain neurotransmitter receptors, voltage and ligand gated ion channels
Term
Axon
Definition
Longer and thicker than dendrite, neurons usually have just one
Term
Synaptic terminals
Definition
rounded ends of the axon, cite where neurotransmitter is stored waiting on an impulse
Term
Nuclei
Definition
Groups of cell bodies in the CNS
Term
Ganglia
Definition
Group of cell bodies in the PNS
Term
Axoplamsic flow
Definition
Moves soluble compounds toward nerve endings via rhythimic contractions of axon; flow is always form cell body to ends
Term
Axonal transport
Definition
Moves large and insoluble compounds bidirectionally along microtubules; viruses and toxins enter CNS this way
Term
Sensory/Afferent, Moter/Efferent, Association/Interneurons, Autonomic motor neuron
Definition
Functional classifications of Neurons
Term
Sensory/Afferent neurons
Definition
Neurons conduct impulses into CNS, all types of sensory info is carried by the same kind of transmission; converts the impulse into sensory impulse
Term
Motor/Efferent
Definition
Neurons carry impulses out of CNS to the body to a muscle or a gland
Term
Association/Interneurons
Definition
Integrate NS activity, Located only in the CNS in the spinal cord or tracts of brain; help integrate all the information
Term
Autonomic motor neurons
Definition
Carry output to smooth muscle, cardiac muscle and glands
Term
Synapse
Definition
junction between two cells
Term
Schwann and satellite cells
Definition
Supporting/Glial cells in the PNS
Term
Schwann cells
Definition
Myelinate PNS axons, form neurilemma, form the myelin sheath
Term
Nodes of Ranvier
Definition
between the Schwann cells allow the faster passage of electrical impulses
Term
Satellite cells
Definition
Repair processes, form of stem cells
Term
myelin sheath
Definition
multilayered lipid and protein covering derived from the cell membrane of Schwann cells in the PNS and oligodendrocytes in the CNS
Term
properties of myelination by Schwann cell
Definition
myelinates 1mm of 1 axon by spiraling membrane round and round axon, 50-100 layers of Schwann cell, inner layer electrically insulates
Term
Neurolemma
Definition
outer, nucleated layer of Schwann cell, housekeeping properties of cell lies here
Term
Glial Cells of the CNS
Definition
Oligodendrocytes, microglia, astrocytes, ependymal cells
Term
Oligodendrocytes
Definition
Responsible for myelinating the axons of CNS neurons making "white matter"; each is involved in myelination of several CNS axons
Term
Multiple sclerosis (MS)
Definition
results from scarring due to demyelination, autoimmune disease that results in the progressive destruction of the myelin sheaths in the CNS
Term
Microglia
Definition
Derived from monocytes, phagocytic cells
Term
Astrocytes
Definition
Largest, most numerous supporting cell in the CNS
Term
Ependymal cells
Definition
specialized epithelial cells lining the central wall and ventricles of the CNS, produce cerebrospinal fluid
Term
Regeneration
Definition
Requires the complex interplay of neurolemma, neutrophins, and Schwann cells, occurs more readily in the PNS than in CNS
Term
Why regeneration does not occur in CNS
Definition
Oligodendrocytes are not removed and secrete inhibitory proteins, no neurolemma so no regeneration tube, astrocytes produce scarring the physically prevents regeneration
Term
Neurotrophins
Definition
chemical messengers that promote fetal nerve growth, required for the maintenance survival of many adult neurons, important in regeneration.
Term
Astrocytes
Definition
Most numerous and largest glial cell in CNS, formation of the Blood-Brain barrier, prevents leakage of K+, convert glucose to lactate for aerobic metabolism, recycling of neurotransmitters, regulates adult neurogenesis
Term
Blood-Brain Barrier
Definition
Capillaries are anatimically differentiated, held together by tight junctions (complex of transmembrane proteins), insures only molecules that are selectively transported
Term
Resting membrane potential (RMP)
Definition
The measured potential difference across the membrane in an non stimulated cell, At rest all animal cells have a negative internal charge: K+ inside, Na+ outside, inside is -70
Term
RMP altered two ways
Definition
A change in the extracellular concentration of one or more of the contributing ions, or a change in the membrane permeability of one or more of the contributing ions
Term
Excitability/Irritibility
Definition
The ability to respond to stimuli by altering membrane permeability thus changing their membrane potential
Term
Depolarization
Definition
Occurs when MP becomes more positive due to the influx of positively charged ions
Term
Hyperpolarization
Definition
MP becomes more negative than RMP due to the efflux of positive charges or the influx of negative charges
Term
Repolarization
Definition
MP returns to RMP due to the efflux of positive charges following a depolarization event
Term
MP changes
Definition
occur when the membrane permeability for specific ions is altered by the opening and closing flow of ion-specific membrane channels
Term
Voltage-gated (VG) channels
Definition
opened by depolarization
Term
Action Potential
Definition
Cycle of depolarization and repolarization and is the basis of the nerve impulse, wave of MP change that sweeps along the axon from the axon hillock at the base of the soma to the terminal boutons of the collateral axon branches
Term
Threshold potential
Definition
degree of depolarization of the RMP required to activate VG channels and initiate an action potential (-55mV)
Term
Depolarization events
Definition
At threshold potential VG Na+ channels open, changed MP to +30 mV
Term
Repolarization events
Definition
VG Na+ channels close, VG K+ channels open, electrochemical gradient drives K+ outward, repolarizes axon to RMP
Term
All or None
Definition
When MP reaches threshold, an AP is irreversibly fired, you can increase the frequency but not the amplitude of AP in a single axon
Term
Synapse
Definition
Functional connection between a neuron and another cell
Term
Electrical Synapse
Definition
Depolarization flows from presynaptic into postsynaptic cell through channels called gap junctions, found in smooth and cardiac muscles, brain, and glial cells
Term
gap junctions
Definition
formed by connexin proteins
Term
Synaptic cleft
Definition
separates terminal bouton of presynaptic from postsynaptic cell
Term
Chemical synapse
Definition
Action potentials reach axon terminal, Ca2+ in cytoplasm activates calmodulin, activates protein kinases leading to fusion of vesicles with plasma membrane, pore forms in fused vesicle and exocytosis releases neurotransmitter
Term
Synaptic transmission
Definition
NT (ligand) diffuses across cleft, binds to receptor proteins on postsynaptic membrane, chemically regulated ion channels open
Term
EPSP
Definition
Excitatory postsynaptic potential, depolarization channels cause
Term
IPSP
Definition
Inhibitory postsynaptic potentials, hyperpolarizing channels cause
Term
Neurotransmitters
Definition
Specific chemicals produced by neurons that are released in a regulated way in order to communicate with an adjacent cell
Term
Acetylcholine
Definition
Made from non polar pre-structure with an acetyl group, most widely used NT, NT at all neuromuscular junctions, used in brain, in ANS can be excitatory or inhibitory
Term
Ligand-Operated Channels
Definition
Ion channel runs through receptor, opens when ligand (NT) binds
Term
Nicotinic ACh channel
Definition
Found in skeletal muscle at motor implate and on neurons that synapse with ACh releasing neurons, formed by 5 polypeptide subunits, opens when 2 AChs bind, permits diffusion of Na+ in and K+ out of postsynaptic cell, produces EPSPs
Term
G Protein-Operated Channels
Definition
Made of alpha, beta and gamma polypeptides, activates when alpha separates, receptor is not part of the ion channel, ligand gated molecule
Term
Muscarinic ACh channel
Definition
Mushroom toxin can bind receptor, binding of 1 ACh activates G-protein cascade, opens some K+ (hyperpolarization), closes others causing depolarization, ACh binding causes IPSPs, in cardiac muscle cells the G proteins open the K+ channel causing EPSPs
Term
Acetylcholinesterase (AChE)
Definition
Inactivates Ach, terminating its action; located in cleft
Term
Monoamine NTs
Definition
Serotonin, norepinephrine, and dopamine
Term
Serotonin
Definition
derived from tryptophan, involved in regulation of mood, behavior, appetite, and cerbral circulation, LSD is strucutally similar
Term
SSRIs (serotonin-specific reuptake inhibitors)
Definition
include antidepressants (Prozac, Zolof, Paxil, Luvox), block reuptake of serotonin, prolonging its action
Term
Dopamine
Definition
Involved in motor control and emotional reward, schizophrenia treated by anti-dopamine drugs, receptors can be bound by cocaine and alcohol
Term
Parkinson's disease
Definition
caused by degeneration of dopamine motor system neurons
Term
Nigrostiatal dopamine system
Definition
regulated fine muscle activity
Term
Mezolimbic system
Definition
ring of neurons around the brain stem that are important in our behavior reward system
Term
Norepinephrine (NE)
Definition
Used in PNS and CNS, sympathetic NT in PNS, affects general leve of arousal in CNS, amphetamines stimulate NE pathways
Term
Amino Acid NTs
Definition
Glutamic acid, aspartic acid, glycine, GABA
Term
Glutamic acid/aspartic acid
Definition
Major CNS excitatory NTs, NMDA receptors have to bind both at the same time, memory storage
Term
glycine
Definition
inhibitory NT, opens Cl- channels which hyperpolarize, strychnine blocks glycine receptors, inhibits antagonistic muscle fibers
Term
GABA
Definition
(gamma-aminobutyric acid) most common NT in brain, inhibitory, opens Cl- channels
Term
Polypeptide NTs (Neuropeptides)
Definition
Cause wide range of effects, not thought to open ion channels, neuromodulators, involved in learning and neural plasticity
Term
CCK
Definition
Neuropeptide that promotes satiety following meals
Term
Substance P
Definition
Neuropeptide that is a pain NT
Term
Endorphins, enephalins, and dynorphins
Definition
Neuropeptides, analgesics, effects are blocked by naloxone (opiate antagonist), andogenous opiods (poppy plants)
Term
Neuropeptide Y
Definition
Most common neuropeptide, inhibits glutamate in hippocampus, powerful stimulator of appetite
Term
Endocannabinoids
Definition
neuropeptides, similar to THC in marijuana, only lipid NTs, have analgesic effects
Term
NO and CO
Definition
gaseous NTs, act through cGMP second messenger system, NO causes smooth muscle relaxation, viagra increases NO, causes small vessel to enlarge to increase blood flow, neither bind to receptor
Term
EPSPs
Definition
Graded in magnitude, have no threshold, cause depolarization, summate, have no refractory period
Term
Spatial Summation
Definition
Takes place when EPSPs from different synapses occur in postsynaptic cell at the same time
Term
Temporal Summation
Definition
occurs because EPSPs that occur closely in time can sum before they fade, frequency of neurotransmitter release from a postsynaptic neuron
Term
Synaptic Plasticity
Definition
Repeated use of a synapse can increase or decrease its ease of transmission
Term
Postsynaptic inhibition
Definition
GABA and glycine produce IPSPs, IPSPs dampen EPSPs making it harder to reach threshold
Term
Presynaptic inhibition
Definition
Occurs when one neuron synapses onto axon or bouton of another neuron inhibiting release of its NT
Term
Brain
Definition
integration and control of neurological activity
Term
Spinal cord
Definition
tracts of nerves that relay sensory and motor information between the brain and somatic structures
Term
Functions of CNS
Definition
Received input from sensory neurons concerning incoming stimuli, association neurons integrate sensory and motor activity in order to maintain homeostasis, perform learning and memory so that behavior can be modified to aid in survival, directs activity of motor neurons
Term
Gray matter
Definition
consists of neuron bodies and dendrites (unmyelinated tissue)
Term
White matter
Definition
Consists of axon tracts (myelinated)
Term
Brain facts
Definition
Adult brain weighs 1.5 kg (almost 3lb), Contains 100 billion neurons, received 20% of blood flow to body
Term
Embryonic development - Week 3
Definition
day 14-15 gastrulation occurs, cells of embryonic disc develop into 3 layers
Term
Epiblast
Definition
(embryonic disc) invaginates forming the endoderm which develops into the epithelial lining of the GI and respiratory tracs, circulatory system and other viscera
Term
Mesoderm
Definition
(embryonic disc) develops into all skeletal, cardiac, and most smooth muscle, bone and blood cells and other connective tissues
Term
Ectoderm
Definition
(embryonic disc) embryonic tissue that covers the surface of the embryo and eventually develops into epidermis of skin and nervous system
Term
Neurulation
Definition
induced by the notochord that results in thr formation of the neural plate, neural folds, and neural tube (week 3)
Term
Neural tube
Definition
forms from invagination along the dorsal midline forming a groove in the ectoderm by 20th day, fusion of the ectoderm forms a hollow neural tube that becomes the CNS
Term
Neural crest cells
Definition
develop where the neural tube fuses, become ganglia of PNS
Term
4th week of embryonic development
Definition
all of the major organs begin to appear
Term
3 swellings form on the neural tube
Definition
these become the forebrain (Prosencephalon), midbrain (Mesencephalon), and hindbrain (Rhombencephalon)
Term
5th week of development
Definition
Brain develops rapidly, head size increases, Forebrain separates into telencephalon and diencephalon, midbrain does not divide, hindbrain forms metencephalon and myelencephalon
Term
Ventricles and Central canal
Definition
remnants of hollow part of neural tube, contain cerebral fluid (CSF)
Term
Brain organization
Definition
Telencephalon (cerebrum), Diencephalon, Mesencephalon (midbrain), Mentencephalon (hindbrain), Myelencephalon
Term
Cerebrum (Telencephalon)
Definition
largest part of brain (75-80% of mass), responsible for higher brain functions, right and left hemispheres interconnected by corpus collosum
Term
White matter in cerebrum
Definition
Composed of association fibers between gyri in same hemisphere, Commissural fibers from one hemisphere to another, Projection fibers from descending and ascending tracts
Term
Outer cortex
Definition
2-4 nm layer of unmyelinated cell bodies that overlays the myelinated axon tracts or white matter and the basal nuclei
Term
Cerebral cortex
Definition
Highly convoluted with numerous elevations (gyri), depressions (sulci), and crevices
Term
Cerebral hemispheres
Definition
organized into 5 lobes based on the anatomic position of large grooves and fissures that define the boundaries of the lobes
Term
Central Sulcus
Definition
Separates the Frontal lobe from the parietal lobe
Term
Central sulcus
Definition
separates the fronal and parietal lobes from the temporal lobe
Term
Precentral gyrus
Definition
of the frontal lobe, is a prominent gyrus anterior to the central sucus that is involved in motor control
Term
Post central gyrus
Definition
of the parietal lobe, receives sensory information from cochlea
Term
Temporal lobe
Definition
contains auditory centers; receives sensory info from cochlea, also links and processes auditory and visual info
Term
Occipital lobe
Definition
responsible for vision and coordination of eye movements
Term
Insula
Definition
Plays role in memory encoding, integrates sensory info with visceral responses, coordinates cardiovascular response to stress, implicated in nicotine addiction
Term
X-ray computed tomography (CT)
Definition
visualizes soft tissues
Term
Positron-emission tomography (PET)
Definition
used to examine brain metabolisma dn blood flow, drug distribution
Term
Magnetic resonance imaging (MRI)
Definition
shows brain function
Term
Electroencephalogram (EEG)
Definition
measures electrical activity of cerebral cortex, used to diagnose epilepsy and brain death
Term
EEG waves
Definition
Alpha, beta, theta, delta
Term
Alpha waves
Definition
recorded from parietal and occipital lobes with person awake, relaxed, eyes closed
Term
Beta waves
Definition
are strongest from frontal lobes; evoked by visual stimuli and mental activity
Term
Theta waves
Definition
come from temporal and occipital lobes, common in newborns, indicate severe emotional stress in adults
Term
Delta waves
Definition
are from cerebral cortex, common during adult sleep and awake infants, indicates brain damage in awake adults
Term
Basal Nuclei(basal ganglia)
Definition
Distinct masses of cell bodies located deep inside cerebrum, function in control of voluntary movement, neurons regulate the motor output initiated by the upper motor (corical) neurons of the pre-central gyrus
Term
Cortical neurons
Definition
refer to those cells whose soma are located in the cerebral cortex, axons complete motor circuits between the cortex, the basal nuclei, the thalmus, and ultimately the cortex
Term
types of basal nuclei
Definition
Claustrum, corpus striatum
Term
Corpus striatum
Definition
Lentiform nucleus (putamen and globus pallidus), and Caudate nucleus
Term
Basal nuclei
Definition
activated by excitatory NT glutamate released by cortical neurons, release the NT GABA which inhibits neurons in the thalamus, the thalamic neurons complete the circuits by releasing excitatory NTs at synapses with cortical neurons
Term
Substantia nigra
Definition
Nucleus found in the midbrain, contains both GABA-releasing and Dopamine-releasing neurons that help to regulate voluntary motor, GABA projects to the Thalamus, Dopamine projecto the basal nuclei in the corpus striatum
Term
Cerebral Lateralization
Definition
refers to specialization of each hemisphere for certain functions
Term
Hemisphere controls
Definition
each controls movement on opposite side of body and receives sensory info from opposite side of body
Term
Hemisphere communication
Definition
communicate through the corpus callosum
Term
Motor output and Sensory input
Definition
tavel tracts the decussate (cross-over) so that motor output initiated in one hemisphere controls the effectors on the contralateral side of the body and somatesthetic sensations received by neurons in post central gyrus on contralateral side of brain
Term
Hemisphere domination
Definition
Rather than one being dominant, each hemisphere appears to be specialized to perform certain tasks while the other hemisphere is specialized to perform different functions that supports or compliments the other
Term
Left hemisphere
Definition
specialized in language abilities and analytical skills
Term
Right hemisphere
Definition
specialized for visuospatial activities, recognition of patterns, part-whole relationships, creative abilities; artistic, music composition
Term
Language
Definition
Areas of brain known mostly from aphasias, speech and language disorders due to brain damage
Term
Broca's area
Definition
necessary for speech
Term
Wernicke's area
Definition
involved in language comprehension
Term
Emotion and motivation
Definition
Originate largely in hypothalamus and limbic system, include aggression, fear, feeding, sex, and goal-directed behaviors
Term
Memory
Definition
Ability to recall previous events, a form of survival learning
Term
Cerebral hemispheres, hippocampus, amygdala
Definition
parts of brain associated with memory
Term
Amnesia
Definition
(memory loss) studies reveal separate short and long term memory systems
Term
Stimulus response memory
Definition
Most animals do; even some protists
Term
Declarative memory
Definition
recalling of specific facts and events
Term
Long term memory
Definition
requires biochemical events that result in LTP
Term
Hippocampus
Definition
critical for acquiring new memories and consolidating short into long-term memory
Term
Amygdala
Definition
Crucial for fear memories
Term
Prefrontal cortex
Definition
higher order processing and planning occur
Term
Cerebral hemispheres
Definition
Storage of memory here
Term
Left-medial temporal lobe
Definition
seems to be speicalized in storing verbal memories
Term
Right medial temporal lobe
Definition
specialized for non verbal memories (visual)
Term
Long-Term Potentiation (LTP)
Definition
Increased excitability of a synapse after high frequency stimulation, Glutamate activates AMPA and NMDA post synaptic receptors in hippocampus, glycine or serine coactivate NMDA opening Ca2+ channesl, Ca2+ levels increase causing NT release, form of synaptic learning
Term
Neurogenesis in Hippocampus
Definition
Crucial for learning and memory, hippocampus contains neural stem cells, stress causes hippocampus to shrink
Term
Thalamus
Definition
located at base of cerebral hemispheres, relay center thru which all sensory info passes to cerebrum, plays role in level of arousal
Term
Epithalamus
Definition
Contains choroid plexus (system of capillaries) which secretes CSF, also contains pineal gland which secretes melatonin, involved in sleep cycle and seasonal reproduction
Term
hypothalamus
Definition
Most important structure for homeostasis; contains neural centers for hunger, thirst, and temp; regulates sleep, emotion, sexual arousal, anger, fear, pain, and pleasure, controls hormone release from anterior pituitary, produces ADH and oxytocin, coordinates sympathetic and parasympathetic actions
Term
Pituitary Gland
Definition
Divided into anterior and posterior lobes; posterior lobe stores and releases ADH and oxytocin (made in hypothalamus and transported
Term
hypothalamus
Definition
produces releasing and inhibiting hormones that control anterior pituitary glands
Term
Circadian rhythms
Definition
Body's daily rhythms, regulated by SCN (suprachiasmatic nucleus) of hypothalamus; master clock adjusted daily by light from eyes; controls pineal gland secretion of melatonin (regulates)
Term
Midbrain
Definition
Contains corpora quadrigemina (4 nuclei involved in visual and auditory reflex responses), red nucleus and substantia nigra, and mesolimbic dopamine neurons
Term
Red nucleus and substantia nigra
Definition
involved in motor coordination; S.nigra dopamine neurons degenerage in Parkinson's
Term
Mesolimbic dopamine neurons
Definition
involved in reward and addiction
Term
Hindbrain
Definition
Contains pons, cerebellum and mudulla
Term
Pons
Definition
Contains nuclei of cranial nerves that innervate the structures in the head and face; site of apneustic and pneumotaxic respiratory control centers
Term
cerebellum
Definition
2nd largest structure in the brain (100 billion neurons); receives input from proprioceptors; involved in coordinating movements and motor learning
Term
Medulla
Definition
Contains all tracts that pass between brain and spinal cord, many nuclei of cranial nerves, and several crucial centers for breathing and cardiovascular systems
Term
Reticular formation
Definition
Complex network of nuclei and fibers spanning medulla, pons, midbrain, thalamus, and hypothalamus; functions as reticular activating system, sets levels of arousal of cerebral cortex to incoming sensory information
Term
Spinal Cord Tracts
Definition
Sensory info from body travels to brain in ascending tracts, motor activity from brain travels to body in descending tracts
Term
Ascending spinal tracts
Definition
decussate so that brain hemisphers receive info from opposite sides of body
Term
Pyramidal or corticospinal descending tracts
Definition
descend directly without synaptic interruption from cerebral cortex to spinal cord, function in control of fine movements
Term
Reticulospinal or extrapyramidal descending tracts
Definition
descend with many synapses, influence movement indirectly
Term
Cranial Nerves
Definition
consists of 12 pairs of nerves: 2 pairs arise from neurons in forebrain, 10 pairs arise from midbrain and hindbrain neurons, and most are mixed nerves containing both sensory and motor fibers
Term
Spinal Nerves
Definition
Mixed nerves that separate next to spinal cord into dorsal (sensory fibers) and ventral roots (motor fibers); 31 pairs
Term
Types of spinal nerves
Definition
8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
Supporting users have an ad free experience!