1. Why are the testosterone-like drugs that athletes abuse called "anabolic" steroids?

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 blood volume

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 cell

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 winner

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 open, activate)

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 action potential

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?

parasympathetic, acetylcholine

26. What is the mechanism for hyperpolarization in an inhibitory postsynaptic potential (IPSP)?

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 calmodulin

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?

dopamine, norepinephrine

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 for cGMP

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)?

superoxide dismutase

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 calcium concentration?

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 skeletal muscle?

muscle glycogen

43 What is the function of the gamma motor neuron?

preset the stretch of the stretch receptor via the nuclear chain (intrafusal) muscle

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 calcium channels

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 for energy?

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 conditions?

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 of ATP.

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