Term
|
Definition
| Which endocrine gland shrinks during growth? |
|
|
Term
|
Definition
| Which of the following is a secondary endocrine organ? |
|
|
Term
|
Definition
| What is a function of the thymus? |
|
|
Term
|
Definition
| The hormone ACTH, released form the anterior pituitary is involved in the action of? |
|
|
Term
|
Definition
| Which hormone targets the kidney and is made in the adrenal cortex? |
|
|
Term
1. neuromuscular excitability
2. excitation and contractability in cardiac and smooth muscle
3. stimulus for secretion
4. maintain tight junctions between cells |
|
Definition
|
|
Term
|
Definition
| Which anterior pituitary hormone is responsible for making testosterone? |
|
|
Term
|
Definition
| Hashimoto’s disease is linked to... |
|
|
Term
|
Definition
| There are more _____________ in the nervous sytem. |
|
|
Term
|
Definition
| What is the typical neuron 25 times more permeable to? |
|
|
Term
|
Definition
| What gate is time dependent and closes with depolarization? |
|
|
Term
| has a better chance of getting its messages through |
|
Definition
| An axon terminal that is closest to the hillock... |
|
|
Term
|
Definition
| Leak channels are ion channels in neurons that are... |
|
|
Term
|
Definition
| When a membrane is at resting potential, sodium and chloride ions are distributed _____________ the cell. |
|
|
Term
|
Definition
| Which glial cell secretes EPO for increased oxygenation of the brain? |
|
|
Term
| threshold depolarizes AP & suprathreshold depolarizes AP |
|
Definition
| What is true about All-or-None Principle of threshold? |
|
|
Term
| communicate over short distances & their magnitudes vary with strengths of stimulus |
|
Definition
|
|
Term
|
Definition
| What is the type of synapse composed of two neurons linked together by gap junctions? |
|
|
Term
don't diminish across membrane, are always depolarized, can be summed.
not true: no refractory |
|
Definition
|
|
Term
| blocking ACH receptors & preventing muscle contractions |
|
Definition
| Botolism toxin type A works by... |
|
|
Term
|
Definition
| Which substance does cocaine block the reuptake of? |
|
|
Term
|
Definition
| _______________ may have multiple targets |
|
|
Term
|
Definition
| Where are calcium gate voltage-gated? |
|
|
Term
|
Definition
| Excitatory post synaptic potentials lead to greater... |
|
|
Term
| voltage gated Ca++ channels open |
|
Definition
| What is the second step of communication across a synapse? |
|
|
Term
|
Definition
| 26. The major excitatory neurotransmitter in the brain is... |
|
|
Term
|
Definition
| ______________ is the term used when there is blocked drainage in the brain. |
|
|
Term
|
Definition
| What physically supports the CNS? |
|
|
Term
headache, blindness, & convulsions
NOT: nosebleeds |
|
Definition
| What are signs of a stroke? |
|
|
Term
logic, analytical abilities, better language skills, muscles on the right side of the body
NOT: spacial perception |
|
Definition
| What does the left side of the brain specialize in? |
|
|
Term
|
Definition
graded or action?
--behaves in all-or-none fashion |
|
|
Term
|
Definition
graded or action?
magnitude of the potential change varies with the magnitude of the triggering response |
|
|
Term
|
Definition
graded or action?
decremental spread away from the original site |
|
|
Term
|
Definition
graded or action?
spreads throughout the membrane in nondiminishing fashion |
|
|
Term
|
Definition
graded or action?
serves as a long-distance signal |
|
|
Term
|
Definition
graded or action?
serves as a short-distance signal |
|
|
Term
| peripheral nervous system |
|
Definition
| consists of nerves carrying information between the periphery and the CNS |
|
|
Term
|
Definition
| consists of the brain and spinal cord |
|
|
Term
|
Definition
| division of the peripheral nervous system that transmits signal to the CNS |
|
|
Term
|
Definition
| division of the peripheral nervous system that transmits signals from the CNS |
|
|
Term
|
Definition
| supplies skeletal muscles |
|
|
Term
|
Definition
| supplies smooth muscle, cardiac muscle, and glands |
|
|
Term
|
Definition
T/F?
Conformational changes in channel proteins brought about by voltage changes are responsible for opening and closing Na+ and K+. |
|
|
Term
F
effluxes of K+ repolarizes membrane |
|
Definition
T/F?
The Na+ -K+ pump restores the membrane to resting potential after it reaches the peak of an action potential. |
|
|
Term
False
presynaptic neurons do this |
|
Definition
T/F?
Postsynaptic neurons can either excite or inhibit presynaptic neurons. |
|
|
Term
False
major function=cushion |
|
Definition
T/F?
The major function of the CSF is to nourish the brain. |
|
|
Term
|
Definition
T/F?
The brain can perform anaerobic metabolism in emergencies when O2 supplies are low. |
|
|
Term
|
Definition
T/F?
The hands and structures associated with the mouth have a disproportionately large share of representation in both the sensory and motor cortexes. |
|
|
Term
|
Definition
T/F?
One hormone may influence more than one type of target cell. |
|
|
Term
False
Ex. pancreas
--can be endocrine pancreas AND exocrine pancreas |
|
Definition
T/F?
All endocrine glands are exclusively endocrine in function. |
|
|
Term
|
Definition
T/F?
“Male” sex hormones are produced in both males and females by the adrenal cortex. |
|
|
Term
|
Definition
|
|
Term
Magnitude diminished with depth, No refractory, Can be depolarized or hyperpolarized
False: No summation |
|
Definition
| All about graded potentials |
|
|
Term
|
Definition
| _________ is an amino acid neurotransmitter at excitatory synapse. |
|
|
Term
|
Definition
| __________ neurons release norepinephrine |
|
|
Term
| salivary gland secretions |
|
Definition
| An example of a complementary effect would be... |
|
|
Term
|
Definition
| Muscle cells are stored in bundles known as __________. |
|
|
Term
|
Definition
| The ____________ is the delay of a few milliseconds that occurs between the action potential in a muscle cell and the start of contraction, where the cell first begins to generate force. |
|
|
Term
|
Definition
| When a muscle shortens during contraction it is contracting... |
|
|
Term
|
Definition
| The Basal nuclei receive and give motor information via the... |
|
|
Term
|
Definition
| The amount of neurotransmitter released depends on the concentration of _________ ion in the cytosol of the axon terminal. |
|
|
Term
| Development of neural connections, Remove neurotransmitter from synaptic cleft, Communicate to neurons through chemical messengers, Protect neurons against toxic substances and oxidative stress |
|
Definition
| What are the properties of astrocytes? |
|
|
Term
| Time required for calcium to trigger the exocytosis of NT |
|
Definition
| What is the cause of the synaptic delay during synaptic communication? |
|
|
Term
|
Definition
| What is a specialized region of the muscle fiber’s plasma membrane that has invaginations containing large numbers of nicotinic cholinergic receptors? |
|
|
Term
|
Definition
| ___________ stays the same length during a muscle contraction. |
|
|
Term
|
Definition
| Information transported by the periphery is brought to the CNS by ___________ pathways? |
|
|
Term
|
Definition
| After Ca+ is released from the sarcoplasmic reticulum, which of the following does it bind to first? |
|
|
Term
|
Definition
| What neurotransmitter is released to trigger the parasympathetic response? |
|
|
Term
High glycolytic capacity, No myoglobin, Slow to fatigue, High myosin ATPase activity
NOT: large diameter |
|
Definition
| What are the properties of fast glycolytic fibers? |
|
|
Term
True
Ex. anterior pituitary |
|
Definition
T/F?
A single gland may produce multiple hormones. |
|
|
Term
True
EX. Somatostatin (stomach, pancreas, and hypothalamus) |
|
Definition
T/F?
A single hormone may be made by more than one gland |
|
|
Term
| may have more than one target & response, some organs may be exclusively hormonal (anterior pituitary) while some organs produce hormones and have other functions (testes produce testosterone and sperm) |
|
Definition
|
|
Term
Hypothalamus
Pituitary glands
Pancreas
Gonads
Pineal gland
Thyroid gland
Parathyroid glands
Thymus
Adrenal glands |
|
Definition
List the endocrine organs:
(9) |
|
|
Term
|
Definition
| stem that leads from the hypothalamus to the pituitary gland |
|
|
Term
secretes ADH (conserves H2O and regulates H2O distribution to kidneys), secretes oxytocin (stimulates uterine contractions 'partuition, ejects milk from breasts)
called the "love hormone"
--women who are nursing/pregnant |
|
Definition
| What does the posterior pituitary do? |
|
|
Term
| secretes tropic hormones (can be stimulating or inhibiting; they are hormones that regulate the secretion of other hormones) |
|
Definition
| What does the anterior pituitary do? |
|
|
Term
T: breast
A: milk production
anterior pituitary |
|
Definition
Hormone: Prolactin
Target/Action? |
|
|
Term
T: adrenal cortex
A: release corticoids (tropic)
anterior pituitary |
|
Definition
Hormone: ACTH
Target/Action? |
|
|
Term
T: bones & muscles
A: growth in length
anterior pituitary |
|
Definition
Hormone: GH
Target/Action? |
|
|
Term
T: thyroid gland
A: release T3 & T4 (tropic)
anterior pituitary |
|
Definition
Hormone: TSH
Target/Action? |
|
|
Term
T: Leydigs cells
A: make testosterone (tropic)
anterior pituitary |
|
Definition
Hormone: LH (male)
Target/Action? |
|
|
Term
T: follicle
A: ovulation (tropic)
anterior pituitary |
|
Definition
Hormone: LH (female)
Target/Action? |
|
|
Term
T: testes
A: Spermatogenesis (tropic)
anterior pituitary |
|
Definition
Hormone: FSH (male)
Target/Action? |
|
|
Term
T: ovaries
A: maturation of ova (tropic)
anterior pituitary |
|
Definition
Hormone: FSH (female)
Target/Action? |
|
|
Term
Tropic Hormone: GH
GH stimulates somatomedins (insulin-like growth factors 'IGFs') to be released by live/other cells..direct effect |
|
Definition
| Example of a tropic hormone |
|
|
Term
common in:
-Elderly white women “dowager’s hump”
-Smokers
-Short people
-Person’s lacking Calcium in diet in teens-20
-People who have low body weight due to exercise
dexa- scan used in disgnosis |
|
Definition
Clinical Aspect of anterior pituitary:
Osteoporosis |
|
|
Term
- hypersecretion of GH in children
-Generally due to anterior pituitary tumors
-After puberty= thickened bones in jaw, hands and feet, increase in size of internal organs |
|
Definition
Clinical Aspect of anterior pituitary:
Gigantism |
|
|
Term
| hypersecretion of GH in adults |
|
Definition
Clinical Aspect of anterior pituitary:
Acromegaly |
|
|
Term
| secretes T3 & T4 (regulates metabolism, necessary for normal growth/development, alters transcription, increases rate of Na+/K+ pump), also secretes calcitonin (regulates calcium levels but not the critical hormone for calcium metabolism)) |
|
Definition
| What does the thyroid gland do? |
|
|
Term
low plasma levels of TH often due to low iodine consumption.
symptoms: cold intolerance, weight gain, decreased concentration |
|
Definition
Clinical aspect of thyroid gland:
Hypothyroidism |
|
|
Term
Potentiates actions of catecholamines which lead to anxiety, racing heart, nervousness
symptoms: Heat intolerance, weight loss, increased concentration |
|
Definition
Clinical aspect of thyroid gland:
Hyperthyroidism |
|
|
Term
Hashimoto's disease: autoimmune
Cretinism: in infancy; stunted physical/mental growth...due to a maternal nutritional deficiency of iodine
Grave's Disease |
|
Definition
Other Clinical aspects of thyroid gland:
specific hypothyroidism problems |
|
|
Term
are embedded in the lateral lobes of the thyroid gland.
--parathyroid hormone is the only hormone secreted by the parathyroid glands; most important hormone in the control of plasma Ca++ concentration; Stimulated by decreased plasma Ca++ concentration
Parafollicular cells of thyroid secrete calcitonin which lowers concentration of blood Ca++ causing excretion in urine and/or uptake into bones |
|
Definition
| All about parathyroid glands: |
|
|
Term
•Derived from cholesterol
•Obtained from diet (D2) or from skin by UV light (D3)
•Promotes ↑ absorption of Ca++ and phosphate into bone
•Stored in adipose because it is hydrophilic |
|
Definition
| Parathyroid gland: vitamin D2 & D3 |
|
|
Term
-bowed legs in children with hypocalcemia deficiency
-bowed legs in adults with osteomalacia deficiency |
|
Definition
Clinical Aspect of parathyroid glands:
Rickets |
|
|
Term
Ca++
-stored as cystalline in bones and teeth |
|
Definition
| one of most tightly controlled variables in ECF |
|
|
Term
1. Neuromuscular excitability
–Hypocalcemia moves resting potential closer to threshold-->spontaneous muscle spasms leading to asphyxiation
–Hypercalcemia leads to cardiac arythmias
2. Used in excitation & contractability in cardiac & smooth muscles
–ECF Ca++ triggers heart contractions
3. Stimulus for secretion
–Entry of ECF Ca++ triggers NT release
4. Maintains tight junction between cells
–Intracellular cement
5. Blood clotting factor in clotting cascade
6. Structural matrix in bones & teeth
7. ICF Ca++ = intracellular messenger |
|
Definition
| What are the roles of Ca++? |
|
|
Term
| secretes thymosin (Regulates T cell function, important in immune system function in babies to young adults) |
|
Definition
|
|
Term
| secretes melatonin (Production stimulated by the suparchiasmatic nucleus (SCN) in hypothalamus. Secreted at night during sleep, May inhibit GnRH, Used to treat jetlag) |
|
Definition
| What does the pineal gland do? |
|
|
Term
secretes:
-Mineralocorticoids-(aldosterone)regulates sodium and potassium levels
–Glucocorticoids-(cortisol)regulates body’s response to stress;regulates metabolism
-Androgens-(sex hormones)regulates reproduction functions |
|
Definition
What do the adrenal glands do?
3 Adrenocorticoids (hormones of adrenal glands) |
|
|
Term
| includes acinar cells and duct cells that secrete fluid and enzymes into digestive tract |
|
Definition
| What does the exocrine pancreas do? |
|
|
Term
consists of cell clusters called Islets of Langerhans which is the source of 2 major hormones:
-insulin: secreted by beta cells (B cells)
-glucagon: secreted by alpha cells (a cells)
--both are important in regulation of energy metabolism and blood glucose levels
also another hormone...
-somatostatin: secreted by delta cells (D cells) which regulates digestion and absorption of nutrients; also regulates secretion of other pancreatic hormones |
|
Definition
| What does the endocrine pancreas do? |
|
|
Term
endocrine & nonendocrine functions
produces gametes (sperm/oocytes) & secretes sex hormones:
-male--Testosterone & Androstenedione (androgens)--in testes
-female--Estradiol b17 (related to estrogens) & Progesterone--in ovaries
---placenta acts as endorcrine gland, secreting estrogens and progesterone |
|
Definition
|
|
Term
-heart (ANP)
-kidneys (EPO-erythroprotein & Renin)
-gastrointestinal tract (stomach-gastrin, small intestines-secretin & cholecytokinin (CCK) & glucose (GIP))
-liver (IGFs-somatomedins)
-skin, liver, kidney (1,25-dihydroxy vitamin D3) |
|
Definition
What are the secondary endocrine organs and their hormone(s)?
(5) |
|
|
Term
•More common in northern latitudes (alaska)
•Lack of sunshine in winter brings on the “blues”
•Treat with light box therapy |
|
Definition
Clinical Aspect of the secondary endocrine organs:
Seasonal Affective Disorder |
|
|
Term
|
Definition
| concentration of H+ is higher in ECF than ICF. H is moved out of cell using... |
|
|
Term
| consists of brain and spinal cord which receives and processes information from sensory organs and the viscera to determine the state of the external environment (sensory info) and internal environment (visceral info; it integrates this info and makes decisions on appropriate actions. |
|
Definition
|
|
Term
| consists of neurons (nerves) that provide communication between the central nervous system and organs throughout the body (periphery). |
|
Definition
| What does the peripheral nervous system do? |
|
|
Term
| division of peripheral nervous system where neurons transmit sensory and visceral information from the organs TO the CNS |
|
Definition
| What does the afferent division do? |
|
|
Term
|
Definition
|
|
Term
| vision, hearing, equilibrium, smell, taste |
|
Definition
|
|
Term
division of peripheral nervous system where neurons transmit information FROM the CNS to organs (effector organs) in the periphery
--effector organs (muscles & glands), perform functions in response to commands from neurons; innervate organs (neuron that is capable of transmitting msg's to an effector organ or receiving info from a sensory organ) |
|
Definition
| What does the efferent division do? |
|
|
Term
| branch of efferent division that consists of the motor neurons, which regulates skeletal muscle contractions |
|
Definition
| What does the somatic nervous system do? |
|
|
Term
branch of efferent division that consists of neurons that regulate the function of internal organs, sweat glands, smooth/cardiac muscle, and blood vessels that are not under voluntary control
•Parasympathetic and sympathetic nervous system (further division) |
|
Definition
| What does the autonomic nervous system do? |
|
|
Term
| consists of neurons in the GI tract that can function independently of the rest of the nervous system but communicates with the autonomic nervous system |
|
Definition
| What does the enteric nervous system do? |
|
|
Term
| "excitable cells"--the functional unit, the smallest unit of a tissue that can carry out the function of that tissue |
|
Definition
|
|
Term
| by transmitting electrical impulses – action potentials |
|
Definition
| How do neurons communicate? |
|
|
Term
"support cells"
--–make up 90% of the cells in the nervous system
--Structural and metabolic support |
|
Definition
|
|
Term
1. Sensory (afferent): Incoming messages; conducts impulses TO CNS
2. Motor (efferent): Conducts impulses out of (FROM) CNS to effector; Outgoing messages (contraction-adjust to incoming message)
3. Association (interneurons):Connects sensory to motor; entirely within the CNS (brain and spinal cord); Simple reflex goes just to spinal cord |
|
Definition
| What are the functions of neurons? |
|
|
Term
"cell body" of a neuron
–contains nucleus and most organelles
–although they have a nucleus, mature neurons do not undergo cell division |
|
Definition
|
|
Term
| neural process that extends from soma of a neuron that is the reception of incoming information at specialized junctions called synapses |
|
Definition
|
|
Term
| a presynaptic neuron releases a chemical messenger called a neurotransmitter that usually communicates with the dendrite or cell body of a postsynaptic neuron or other cell |
|
Definition
| What goes on at a synapse? |
|
|
Term
| transmits electrical impulses called action potentials; branches are called "collaterals" |
|
Definition
|
|
Term
| where axon originates and action potentials initiated; any message that comes in through the dendrites has to be strong enough or the message will not be transferred |
|
Definition
|
|
Term
| releases neurotransmitter that are made in the cell body and stored here; releases neurotransmitter on arrival of an action potential |
|
Definition
|
|
Term
| space between a neuron & another cell (another neuron, muscle, or gland) |
|
Definition
|
|
Term
| ion channel that establishes resting membrane potential, is always open, Sodium and potassium ions move through these channels |
|
Definition
| What is a leak channel (nongated)? |
|
|
Term
ion channel that opens or closes in response to ligand binding in the p.m.; almost always found on dendrites & cell body (areas that receive communication from presynaptic neurons in the form of neurotransmitters); Initiate synaptic potentials to move it along
Ex. calcium |
|
Definition
What are ligand-gated channels?
ligand=substance that is binded to a receptor |
|
|
Term
| ion channels that open or close in response to change in membrane potential; voltage-gated Sodium & potassium channels are more densely in the axon and in greatest density in the axon hillock |
|
Definition
| What are voltage-gated channels? |
|
|
Term
| voltage-gate sodium and potassium channels--specifically in axon hillock |
|
Definition
| Where are action potentials initiated? |
|
|
Term
| Initiate release of neurotransmitter or ligand; open in response to the arrival of an action potential at the axon terminals |
|
Definition
| What do voltage-gated calcium channels do? |
|
|
Term
| calcium enters the cytosol of the axon terminals and triggers the release of neurotransmitters |
|
Definition
| What happens when the voltage-gated calcium channels are opened? |
|
|
Term
| sensory neurons with two projections, 1 axon and 1 dendrite, coming off the cell body; Function in smell and vision |
|
Definition
| What are bipolar neurons? |
|
|
Term
| the most common neurons; have multiple projections from the cell body; 1 axon and all the others are dendrites |
|
Definition
| What are multipolar neurons? |
|
|
Term
|
Definition
| ____________account for 99 percent of all neurons in the body; located in CNS; Perform all the functions of the CNS |
|
|
Term
|
Definition
| In the CNS, cell bodies of neurons are often grouped into ______, and the axons travel together in bundles called pathways, tracts, or ___________. |
|
|
Term
|
Definition
| In the PNS, cell bodies of neurons are clustered together in _________ and the axons travel together in bundles called _______. |
|
|
Term
-most abundant glial cell
-found in CNS
-protect brain from foreign substances, regulate external environment of K+ and pH, secrete EPO, release transmitters that communicate to neurons through chemical messengers, remove neurotransmitters from synaptic cleft, maintains normal electrolyte composition in ECF, & protects neurons against toxic substances and oxidative stress |
|
Definition
| What are astrocytes and what do they do? |
|
|
Term
-type of glial cell in CNS
-Secretes CSF (cerebrospinal fluid) and lines ventricles of the brain
-have cilia |
|
Definition
| What do Ependymal cells do? |
|
|
Term
-type of glial cell in CNS
-protect CNS from bacteria & such through phagocytosis (eats debris 'blood bruise') and releasing cytokines
-are migratory
-protects from oxidative stress |
|
Definition
|
|
Term
-type of glial cell in CNS
-one oligodendrocyte forms myelin around several axons of neurons in CNS
-does not repair axons |
|
Definition
| What are Oligodendrocytes and what do they do? |
|
|
Term
| forms a type of insulation around axons of neurons that enables the neurons to transmit action potentials more efficiently and rapidly |
|
Definition
| What is the importance of myelin? |
|
|
Term
-type of glial cell in PNS!!
-each cell only forms 1 myelin around 1 axons of a neuron in PNS
-axon can have many schwann cells
-does repair axon if it has been cut |
|
Definition
| What are Schwann cells and what do they do? |
|
|
Term
-A nerve is a bundle of axons
-A neuron is a single cell |
|
Definition
| What is the difference between a neuron and a nerve? |
|
|
Term
| gaps in the myelin sheath, the axonal membrane contains voltage-gated sodium and potassium channels that function in the transmission of action potentials by allowing ion movement across the membrane |
|
Definition
|
|
Term
-myelin is destroyed primarily on motor neurons by own immune system
-Oligodendrocytes--which cannot be repaired and will get worse
-Most of the damage is next to the CNS |
|
Definition
Clinical Aspect of glial cells:
Multiple Sclerosis |
|
|
Term
-can’t feel sensations or move muscles due to myelin being destroyed on both sensory and motor neurons
-Eventually the myelin will grow back due to Schwann Cells |
|
Definition
Clinical Aspect of glial cells:
Guillain-Barré Syndrome (GBS) |
|
|
Term
|
Definition
| Membrane potentials are always described as the potential _______ the cell relative to _______ |
|
|
Term
False
negative membrane potential |
|
Definition
T/F?
All cells in the body have a positive membrane potential |
|
|
Term
–Approximately -70 mV inside cell
–Exists because more negative charges inside cell and more positive charges outside cell
–Major negative charge inside the cell is due to proteins |
|
Definition
| All about resting membrane potential: |
|
|
Term
| Neurons communicate by generating electrical signals in the form of changes in membrane potential. Some of these changes in membrane potential trigger the release of neurotransmitter, which then carries a signal to another cell |
|
Definition
| How do neurons communicate via resting membrane potential? |
|
|
Term
-ion concentration gradients
-membrane permeability to these ions
–-ion channels |
|
Definition
| What 2 factors are critical in determining the resting membrane potential? |
|
|
Term
-membrane potential is more permeable to K+
-More potassium leaves the cell than sodium enters because of the greater permeability for potassium. With more positive charge leaving the cell, a negative membrane potential develops.
-Electrical force opposes outflow of K+ and favors inflow of Na+, which then stabilizes the large amount of K+ from leaving. |
|
Definition
| Na+/K+ pump vs. membrane potential |
|
|
Term
|
Definition
| –Changes in membrane potential are changes in the degree of ___________ |
|
|
Term
-cell membrane less polarized, less negative relative to surrounding solution
-Gated channels open allowing Na+ to flow in and membrane potential becomes more positive
-Negative – positives come in going up to zero and beyond |
|
Definition
|
|
Term
–cell membrane more polarized, more negative
-K+ moves out of the cell making the cell membrane less positive
-Chloride ions (have a negative charge) move into the cell, hyperpolarizing the membrane |
|
Definition
|
|
Term
| occurs when the membrane potential returns to the resting membrane potential following depolarization |
|
Definition
|
|
Term
|
Definition
| If gated potassium channels open, then potassium moves out of the cell, bringing the membrane potential toward to the potassium equilibrium potential or ___________ the cell |
|
|
Term
|
Definition
| If gated sodium channels open, then sodium moves into the cell, bringing the membrane potential toward the sodium equilibrium potential, or __________ the cell |
|
|
Term
type of potential change that hassmall electrical signals that communicate over short distances, sub-threshold (they do not meet threshold), Strong only next to the immediate stimulus and then it fades away – decreasing with size
–Function is to add enough graded potentials together to become an action potential
–Has a magnitude that varies |
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Definition
| What is a graded potential? |
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Term
| type of potential change that consists of large electrical signals capable of traveling long distances without decreasing in size, supra-threshold (above threshold), always reaches the same height in the same amount of time, never hyperpolarizing, always depolarizing |
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Definition
| What are action potentials? |
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Term
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Definition
Graded/Action?
Initiated by a stimulus (ex: sensory, chemical) that triggers opening or closing of ion channels |
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Term
-Magnitude varies with strength of stimulus (binding of a neurotransmitter or sensory stimulus)
-Weak stimulus-small change in membrane potential; strong stimulus-greater change in membrane potential |
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Definition
| Describe what varying magnitudes of graded potentials means. |
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Term
True
–If one type of neurotransmitter binding to its receptors caused sodium channels to open, then sodium ions would move into the cell and the resulting graded potential would be depolarization
–If another type of neurotransmitter binding to its receptors caused potassium channels to open, then potassium ions would move out of the cell, and the resulting graded potential would be hyperpolarization (inside becomes less positive) |
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Definition
T/F?
Graded potential changes can be hyperpolarizing or depolarizing (below or above resting potentials.) |
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Term
-Determine whether or not an action potential will occur
-have to meet threshold!!! |
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Definition
| What is the purpose of graded potentials? |
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Term
-Determine whether or not an action potential will occur
-have to meet threshold!!! |
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Definition
| What is the purpose of graded potentials? |
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Term
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Definition
| During a(n)________ a large, rapid depolarization occurs in which the polarity of the membrane potential actually reverses and becomes positive for a brief time |
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Term
| along axons from cell body to axon terminal (or if afferent neuron, from receptor to terminal) |
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Definition
| How do action potentials travel in neurons? |
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Term
–Voltage-dependent
–Open sodium channels during depolarization of an action potential
–Positive feedback (As more open, more gates will continue to open) |
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Definition
| How do activation gates work? |
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Term
–Voltage-dependent
–Time-dependent
–Closing of sodium channels during the repolarization phase |
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Definition
| How do inactivation gates work? |
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Term
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Definition
T/F?
For a sodium channel to be open, both gates must be open. |
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Term
| Whether a membrane is depolarized to threshold or above, the amplitude of the resulting action potential is the same; if the membrane is not depolarized to threshold, no action potential occurs. |
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Definition
| What is the "All-Or-None Principle?" |
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Term
| minimum depolarization necessary to induce the regenerative mechanism for the opening of sodium channels |
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Definition
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Term
threshold= action potential
suprathreshold= same action potential
subthreshold= no action potential |
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Definition
| threshold vs. suprathreshold vs. subthreshold action potentials |
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Term
Period of decreased excitability following an action potential (during and immediately after)
absolute-immediately after
relative-after absolute |
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Definition
Refractory period
(2 types) |
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Term
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Definition
| Junction where nerve terminal meets a neuron, muscle cell, or gland |
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Term
| Presynaptic cell (sends signal), synaptic cleft and postsynaptic cell (receives signal) |
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Definition
| Presynaptic vs. Postsynaptic |
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Term
–electrical charge freely flows through gap junctions from cell to cell (brain & heart)
-rapid communication
-bidirectional
-no ligand
-primary excitation
-cannot amplify signal
-Impulses can be regenerated without interruption in adjacent cells
-excitation/inhibition at same synapse |
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Definition
| What is an electrical synapse? |
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Term
–neurotransmitter acts as signal transduction from presynaptic to postsynaptic cell
-Stored in vesicles (hydrophilic)
-Almost all neurons transmit messages to other cells at chemical synapses
-In a chemical synapse, one neuron secretes a neurotransmitter into the extracellular fluid in response to an action potential arriving at its axon terminal. The neurotransmitter then binds to receptors on the plasma membrane of a second cell, triggering in that cell an electrical signal that may or may not initiate an action potential
-A neuron can form synapses with other neurons or with effector cells such as muscle or gland cells. |
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Definition
| What is a chemical synapse? |
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Term
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Definition
| The narrow space between the presynaptic and postsynaptic neurons is called the ____________ |
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Term
1)Action Potential that moves down the axon. When it gets to the bouton, the action potential opens the calcium gates.
2)Voltage-gated Ca channels open (only found in the bouton (end of axon))
3)Calcium triggers exocytosis of the neurotransmitter (NT)
4)NT diffuses and binds to the receptor
5)Response in cell. |
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Definition
| Communication across a synapse: 5 steps |
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Term
-Degredation: certain enzymes break them down
-Reuptake: when the neurotransmitters are actively transported back into the presynaptic neuron that released them
-Diffusion: simply diffused out of the synaptic cleft |
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Definition
| what are 3 ways of moving the neurotransmitters so that we can halt it or send a new one? |
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Term
1)Action Potential that moves down the axon. When it gets to the bouton, the action potential opens the calcium gates.
2)Voltage-gated Ca channels open (only found in the bouton (end of axon))
3)Calcium triggers exocytosis of the neurotransmitter (NT)
4)NT diffuses and binds to the receptor
5)Response in cell. |
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Definition
| Communication across a synapse: 5 steps |
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Term
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Definition
| Change in membrane potential in response to neurotransmitter binding to receptor |
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Term
1. Bone (cranium, vertebrae)
2. Meninges (dura mater, arachnoid mater, pia mater)
3. Cerebrospinal Fluid (CSF)--ECF of CNS |
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Definition
list the physical support of the CNS
(3) |
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Term
–To check CSF for invasion of bacteria or viral particles
–Needle is inserted into subarachnoid space between 3rd and 4th vertebrae (where you find the cerebral spinal fluid) |
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Definition
Clinical aspect of CSF:
Spinal Tap |
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Term
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Definition
–CNS comprises __ of body weight (3-4 pounds)
-Receives __ of blood supply |
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Term
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Definition
-Brain uses ____ of oxygen consumed by body at rest
-Brain uses ____ of glucose consumed by body at rest |
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Term
–Caused by decreased blood supply
-Occlusion of cerebral blood vessel (carotid artery)
-Hemorrhage from cerebral blood vessel
-FAST=face arm speech test
-ABCMH
A aphasia (in left side lesions…hemorrhages on brain)---putting together sentences
B blindness (unilateral)---stroke on left side, right eye is blinded
C coma, convulsions
M mentality changes
H headache and hemipeligia |
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Definition
Clinical aspect of blood supply in CNS:
Strokes |
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Term
| Special anatomy of capillaries in CNS limit exchange between blood and interstitial fluid |
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Definition
| What is the blood-brain barrier? |
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Term
–Gray = cell bodies, dendrites, axon terminals: outer layer of brain
–White = axons inner tracts of brain |
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Definition
| Gray matter vs. white matter |
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Term
–Cylindrical nervous tissue
-Gray matter on inside
-White matter on outside
–Surrounded by vertebral column
–Spinal nerves branch off |
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Definition
| What does the spinal cord consist of? |
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Term
-Cerebral Cortex (alzheimers)
-Basal Nuclei |
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Definition
| What does the cerebrum consist of? |
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Term
-Inhibit unwanted movements
-Selecting purposeful movements
-Where Parkinson’s takes place
-Postural support |
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Definition
| Describe the importance of the basal nuclei |
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Term
-Thalamus
--integrate sensory & motor info
--sensory relay to cortex EXCEPT olfaction
-Hypothalamus |
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Definition
| What does the diencephalon consist of? |
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Term
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Definition
-Motor coordination and balance
-coordination of eye/body movements
-hitting a ball |
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Term
–Connects forebrain and cerebellum
to spinal cord
-Midbrain, connects to forebrain
-Pons, connects to cerebellum
-Medulla, connects to spinal cord
–Processing center for 10/12 cranial nerves
–Reticular formation
–Need to know cranial nerve X (vages nerve |
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Definition
| all about the brain stem: |
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Term
| creativity & spacial perception |
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Definition
| right brain specializations (lateralization): |
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Term
| logic, analytic abilities, language |
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Definition
| left brain specializations (lateralization): |
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Term
-Food intake
-thermoregulation
-Link between nervous & endocrine systems
-Circadian rhythms
–Suprachiasmatic nucleus
–Pineal gland |
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Definition
| all about the hypothalamus: |
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Term
| behavior, emotions, and learning |
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Definition
| what are the functions of the limbic system? |
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Term
feeding
fleeing
fighting
fornication |
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Definition
| what are the 4 f's or survival? |
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Term
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Definition
| to contract a muscle cell... |
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Term
| DO NOT activate motor neuron |
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Definition
| to relax a muscle cell... |
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Term
**Input to brainstem from
-skin receptors
-eyes
-ears
-proprioceptors
-vestibular apparatus |
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Definition
| how posture is controlled: |
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Term
–Dominant genetic disorder of basal nuclei
-Pathway from basal nuclei to thalamus lost
–Symptoms
--Loss of motor coordination
–-Increased involuntary motions
–-Twitches
–-Jerking motions
-Advanced stages- loss of cognitive functions |
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Definition
Clinical aspect of basal nuclei:
Huntington's |
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Term
-Lack of dopamine in substantia nigra
–Symptoms
--Rigidity- slow stiff movements
--Involuntary movements or tremors
--Stooped, shuffling gait
--Difficulty initiating/stopping movements
–Treatments:
–-L-dopa which can be converted into dopamine in the brain
–-Stem cell transplants to replace damaged dopamine secreting neurons |
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Definition
Clinical aspect of basal nuclei:
Parkinson's Disease |
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