1. Why are the testosterone-like drugs that athletes abuse called "anabolic"
one kind of metabolism, anabolic processes, are constructive, and these
drugs build muscle mass
2. What is an ectotherm?
a "cold blooded" animal (whose body is ambient temperature)
3. What is the opposite of vasodilation, and why is this (the opposite of
vasodilation) useful (in terms of homeostasis)?
vasoconstriction would decrease heat loss (body's thermostat)
4. Suppose your metabolic rate (based on size and gender) were 2000 "calories"
(kilocalories) per day. If you ate 2250 "calories" per day for
a year, how would your body deal with that?
you would gain 25 pounds
5. A hormone like estrogen should be terribly inefficient when compared
with a neurotransmitter applied directly to the synapse. The hormone would
be diluted by the entire volume of the circulatory system. What, then, is
the advantage of using hormones as a means of integration?
communication can be to several locations, like from the ovary to the pituitary
plus to the uterus
6. Say something about the unique nature of the transport of thyrotropin-releasing
hormone (TRH) from the site where it is produced to the site where it acts.
goes through a portal blood vessel where it does not get diluted by a large
7. Looking around the room, we see that nobody has goiter. Why not?
even though we live inland, there is plenty of iodine in our diet, seafood
and iodized salt
8. "A semipermeable membrane is part of the explanation for osmosis."
(1) Permeable to what AND (2) not permeable to what?
1-water, 2-larger molecules like glucose, hemoglobin, carbonic anhydrase
9. How is it possible for rhodopsin to reside in the bilayer of phospholipids
with the hydrophobic fatty acids?
the transmenbrane alpha helices have hydrophobic amino acids
10. If you wanted to record the current carried through a single nicotinic
acetylcholine receptor, what technique would you use?
patch clamp, put electrode up to the channel but do not poke it into the
11. What is it called, in bulk transport, when the cell pinches off vesicles
for uptake of substances?
pinocytosis, endocytosis, receptor-mediated endocytosis (maybe some credit
if you mention clathrin)
12. Just for orientation, I will state that, in the phosphoinositide cascade,
the hormone is "upstream" and calcium ions are "downstream."
ANSWER EITHER (1) What is DIRECTLY upstream from the G-protein? OR (2) What
is DIRECTLY downstream from the G-protein?
the G-protein coupled receptor, PLC
13. What would you be hoping to see by making a platinum replica of membranes
that had been frozen and fractured down the middle?
transmembrane proteins like rhodopsin
14. A deliberate slight of hand had me graphing Ohm's law with the X and
Y axes reversed. Thus we talked about "conductance" which relates
to what way of describing how well ions traverse a membrane channel?
15. What does the expression "all-or-none" mean when applied to
the action potential?
you cannot get different sizes of action potentials
16. Who came up with the idea that the chemical gradient is equal and opposite
to the electrical gradient?
that would be the equation attributed to Nernst, the chemistry Nobel prize
17. Why, in the Goldman equation, are In and ut reversed in the numerator
vs the denominator when, in fact, both are high in concentration outside
the cell and low inside?
sodium is a cation while chloride is an anion
(This question was not good. Since.I failed to specify that sodium and chloride
were the focus, I gave credit for the correct answer to everybody.)
18. An axon is depolarized by the application of a "square wave"
of current (i.e. the current is turned on at once). Yet the voltage changes
gradually, giving the membrane the appearance of a low-pass filter. What
property of the membrane makes it this way?
19. Cole and Curtis showed that the resistance decreased during the action
potential. What happens to what channels to mediate this resistance decrease?
conductance increases, sodium channel first then potassium channel (channels
20. "The action potential starts at the axon hillock and goes down
the axon to the terminals." What property of the action potential assures
the unidirectional propagation of the action potential?
refractory period, you cannot generate an action potential right after an
21. "The space constant varies with the square root of the radius."
What does this have to do with the action potential?
giant axons propagate faster in invertebrates
22. Why does paralysis accompany polio?
damage to peripheral nervous system myelin
23. Why did Sherrington consider the spinal motor neuron (rather than the
muscle cell) to be the "final common pathway for the integrative action
of the nervous system?"
that is the last place where excitation AND inhibition can be integrated
24. What is different in the configuration of the sodium channel right after
an action potential (compared with right before)?
inactivated with stopper, vs just closed
25. "Vagus-stuff slows the heart." Answer EITHER (1) What major
subdivision of the autonomic nervous system does vagus-stuff come from?
OR What chemical is vagus-stuff?
26. What is the mechanism for hyperpolarization in an inhibitory postsynaptic
increase in conductance for potassium and chloride
27. After calcium ions come into the synaptic terminal, what do they do
to assist in vesicle release?
bind to synaptotagmin, a vesicle protein, figure also shows calcium activating
28. Some acetylcholine receptors are channels and they are called nicotinic.
The other acetylcholine receptors ANSWER EITHER (1) are what type of signaling
molecule? OR (2) are called by what pharmacological name?
g protein coupled receptor, muscarinic
29. DOPA is the precursor of melanin and what neurotransmitter?
30. What neural function are the substantia nigra, caudate, putamen, basal
ganglia, striatum involved in?
smoothening out motor movements
31. A portion of the parasympathetic output comes from the sacral portion
of the spinal cord. What part of the central nervous system is the source
for the rest of the parasympathetic output?
32. What is the chemical similarity in the actions of caffeine and Viagra?
they are both phosphodiesterase inhibitors, caffeine for cAMP and Viagra
33. Here is a list of 4 places: ganglion and neuro-effector junction for
both parasympathetic and sympathetic nervous systems. List all the places
where the nicotinic receptor is found.
ganglia for both subdivisions of the autonomic nervous system
34. For nitric oxide (NO), answer EITHER (1) What cell does it come from?
OR (2) What enzyme does it activate?
endothelial, guanylate cyclase
35. At 150% of the resting length, a muscle can only generate about half
the tension it generates at 100% resting length. Why?
less overlap between actin and myosin, why it is harder to do a chin-up
from all the way down
36. Why would decreasing extracellular calcium ion concentration allow Nobelist
Sir Bernard Katz to decrease the end plate potential to miniature end plate
potentials each attributable to one "quantum" (vesicle)?
calcium is necessary for vesicle release, and the calcium in the motor neuron's
terminal comes in from outside the cell
37. The power stroke is accompanied by release of (what?) from myosin?
credit for either Pi (inorganic phosphate) or ADP or both
38. What is the name of the band where there is myosin but not actin?
helle (lighter) H band
39. What enzyme functions in your spinal motor neuron but is not functioning
in people with one familial type of ALS (Lou Gehrig's disease)?
40. Nicotinic acetylcholine receptor, skeletal muscle voltage-gated sodium
channel, sarcoplasmic reticulum calcium release channel. What channel is
missing from that list between the end plate and the increase in muscle
transverse tubule voltage-gated calcium channel
41. As phosphocreatine is converted to creatine, what important molecule
necessary for muscle contraction is regenerated?
42. In exercise that is so strenuous that it can only be maintained for
a short duration, what is the predominant source of metabolic energy in
43 What is the function of the gamma motor neuron?
preset the stretch of the stretch receptor via the nuclear chain (intrafusal)
44. How did I get from the activation of myosin light chain kinase (MLCK)
to a therapy to decrease blood pressure?
calcium channel blockers would relax arteriole smooth muscle because calcium
is necessary to activate MLCK and it comes in from outside the cell through
45. Compared with a saturated fatty acid, what must be missing from a carbon
in a fatty acid that has a double bond to its neighboring carbon?
46. H comes from (where?) AND OH comes from (where?) in the dehydration
(condensation) accompanying the formation of a peptide bond?
the amine, the acid
47. Urea is created (ANSWER EITHER) (1) To get rid of what waste? That waste
is created because (2) what kind of molecule is being used by catabolism
ammonia (nitrogen), amino acids
48. In order to regenerate NAD from NADH plus H+, what chemical is converted
to what chemical (ANSWER BOTH) when glycolysis takes place under anaerobic
pyruvic acid into lactic acid
49. "ATP is the universal currency of energy, but it has additional
functions." Using EITHER (1) the beta adrenergic signaling in the liver
cell OR (2) the insulin receptor mechanism, give an example of another function
precursor of cAMP, donate phosphate to tyrosine in tyrosine kinase function
50. GLUT4 increases quickly in the sarcolemma under the influence of insulin.
How can it be so quickly increased?
it is already present in intracellular vesicles that can be quickly deployed
to the cell membrane
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this page was last updated on 9/28/2015