1. Where is the cell body of the muscle stretch receptor in the knee-jerk reflex located?

just outside the spinal cord in the dorsal root ganglion

2. "The basal ganglia are important in motor coordination. Note that basal 'ganglia' is a misnomer." Why is it a misnomer?

because groups of cells in the CNS are officially called "nuclei"

3. What should you ascertain before giving a clot busting blood thinner to reverse a stroke?

that is not a hemorrhage

4. Say something about how the Golgi technique permitted the viewing of the magnificence of a Purkinjee cell in all its glory.

it stains the whole cell a dark color and only stains one out of a zillion cells

5. Say something about the technique used to show that dopamine was in the tract from the substantia nigra to the striatum.

the dopamine was converted to a fluorescent product by exposure of microscope sections to formaldehyde vapor then the slide was viewed in a fluorescence microscope (histochemical fluorescence)

6. My hypothesis is that actin is present in the growing tips of developing axons. I did what the methods handbook suggested, purchasing an antibody produced in goat that is labeled with fluorescein. What other reagent do I need?

a primary antibody against actin produced in mouse to which that secondary antibody can bind

7. Neuroscience class alumnus did some imaging work at Washington University to show that people who were blind from an early age had diminished tracts ANSWER EITHER (1) from where OR (2) to where?

thalamus (lateral geniculate nucleus), visual cortex (area 17)

8. Say something about the protuberances on dendrites where postsynaptic receptors are located.

protuberances are called spines, they have tubulin and actin, they have postsynaptic densities

9. Name one of the proteins involved in axon transport.

kinesin, dynein, microtubular protein

10. Radioactive protein was moved from ganglion cells to where?

thalamus (lateral geniculate nucleus)

11. Why do myelinated axons propagate faster?

the action potential jumps from one node of Ranvier to the next rather than fizzling the whole way along the axon

12. Why is the prefix "oligo" at the beginning of oligodendrocytes?

they myelinate a few axons

13. Why is myelin such a good insulator?

the many membrane layers add resistors and the capacitance adds reciprocally

14. The reason I thought my neuroscience class would be interested in Charcot Marie Tooth (CMT) disease was that I had just talked about polio. Why did our subject JH show us his legs?

like for polio, the loss of motor nerve function led to a deterioration of muscle

15. JH, our CMT subject, had deformed feet since his youth. Why, then, would he rub cream on his feet daily and see a podiatrist every 3 months?

with the neuropathy, sensory loss, he could have a bad wound like the kind that lead to so many amputations from diabetic neuropathy

16. What does the current flow through in Nobelists Neher and Sackman's patch clamp technique?

a single channel

17. "There is a delay in the membrane's voltage response to a sudden step stimulation of current." This is because of what property of the membrane?

it has capacitance

18. "A line describes Ohm's law when it is graphed with current on the Y axis and voltage on the X axis." What is the slope of the line?


19. Why would there be an immediate small (1.5 mV) change in the resting potential when ouabain is applied to the axon?

because 3 sodiums are exchanged for two potassiums, the sodium pump is electrogenic

20. ANSWER EITHER (1) Which side of the membrane is the sodium pump's phosphorylation site? OR (2) Where did that phosphate come from?

inside, ATP

21. Why would a physician prescribe a sodium pump blocker to a patient?

alters the sodium calcium exchanger in myocardial cells resulting in more forceful contractions

22. What is assumed in the derivation of the Nernst equation?

the energies of the two compartments are equal, alternatively that the chemical potential is equal and opposite to the voltage

23. What was the "unknown resistor" in Cole and Curtis's Wheatstone bridge?

the axon membrane

24. Say something about the hormone that makes salt deprived people crave sodium.

aldosterone is from the adrenal cortex, affects sodium retention in the kidney, and there are neurons that are responsive to aldosterone in the taste area of the brain

25. "Hodgkin and Huxley changed the axon voltage then pumped and monitored current to keep that voltage the same." What did they find out by doing that?

the voltage clamp experiments ultimately showed that sodium channels activated then inactivated and then potassium channels activated, and the answer could be that or any statement of conclusions leading to that ultimate conclusion

26. Under what voltage clamp conditions would there be no early component of current in the I-t curves?

when voltage was clamped at the sodium equilibrium (Nernst) potential (the peak of the action potential), also when there was no extracellular sodium

27. "The action potential depolarizes the axon ahead of it to threshold and thus generates an action potential ahead of it." Why doesn't it generate an action potential behind it?

there is a refractory period because the sodium channels are inactivated

28. How was the channel that is mutant in long Q-T syndrome first found as a conditional mutant?

the human ether-a-go-go gene is a homologue of a gene mutated in Drosophila that shake under ether anesthesia

29. "The sodium channel for the action potential is voltage gated." Mechanistically, how does the molecule detect voltage in order to open?

because of the charged (basic) arginines and lysines down one side of the S4 alpha helix, it rotates when the depolarizing voltage arrives

40. CSNB (congenital stationary night blindness): ANSWER EITHER (1) What cells do not work? OR (2) Why is it called "stationary?"

rods, it is not progressive (degeneration) rather blind from birth

41. "The strength of connexin36 synapses is modified by metabotropic glutamate receptors from the neocortex." Elaborate. EITHER (1) Connexin 36 OR (2) Metabotropic.

the particular gap junction protein studied, g protein coupled receptor

42. Why did Sherrington call the spinal motor neuron "the final common pathway of the integrative action of the nervous system?"

at that location, there is integration (of EPSPs and IPSPs) while at the neuromuscular junction, there are only EPPs

43. The resting potential of the postsynaptic neuron is -60 mV. Approximately, what is the value for the reversal potential when a presynaptic GABAergic nerve is stimulated?

-70 mV

44. In vesicle membrane recycling, a coated pit is budded off to a coated vesicle. ANSWER EITHER (1) What protein is necessary? OR (2) This protein is the product of what gene in Drosophila which, if mutated, leads to temperature sensitive paralysis?

dynamin, shibire

45. "Calcium ions are important in synaptic vesicle release." ANSWER EITHER (1) How did calcium concentration increase in the presynaptic cytoplasm? OR (2) What is the name AND location of the protein that binds calcium?

came in through Q or N type voltage gated calcium channels, synaptotagmin on the vesicle

46. Why do you need to really cook the tomatoes and the mason jars?

to kill the endospores of the bacterium that makes botulinum toxin because the bacteria would grow in anaerobic conditions

47. On the vesicle membrane, and also on the presynaptic membrane, there are receptors for "soluable (N-ethylmaleimide sensitive factor) associated protein" during fusion of the vesicle with the membrane. Give a short acronym for that pile of words.


48. What does the gamma in gamma amino butyric acid signify?

instead of having the amine on the alpha carbon where the acid group is, it is on the third carbon

49. What famous protein is the precursor of ACTH, beta-lipotropin, gamma-lipotropin, and beta-endorphin?


50. Why would a muscarinic antagonist save your life if you were poisoned with the insecticide malathion?

acetylcholinesterase inhibitor would stop the heart from too much acetylcholine, so blocking the receptor with atropine would save you

51. Why is it relevant that the substantia nigra is pale in Parkinson's disease?

l-DOPA is a common precursor of melanin and dopamine

52. Rationalize why MAO inhibitors would serve as antidepressants.

norepinephrine is an "upper" and preventing its breakdown would potentiate its action

53.What type of neurotransmitter receptor is used at sympathetic and parasympathetic ganglia?

nicotinic acetylcholine receptors, ionotropic, ligand-gated channels

54. What is the mechanism of action of Viagra?

it inhibits the cGMP PDE

55. What is the mechanism of action of the antidepressant Prozac?

it is a selective serotonin reuptake inhibitor

56. What transmitter is the precursor of melatonin?


57. What is the fate of glutamate removed from the synaptic cleft by glial cells?

it is converted to glutamine which, in turn, is sent back to the nerve terminal for glutamate synthesis

58. Why, when giving l-DOPA therapy, would you also administer an aromatic amino acid decarboxylase inhibitor also?

because DOPA decarboxylase is all over the place, and not much l-DOPA would cross the blood brain barrier to be converted to dopamine to help Parkinson's patients

59. "The lateral hypothalamus must be a hunger center since lesioning it makes the rat lose weight." What is a more modern explanation?

there is a generalized loss of motivation (affect) since the nigro-striatal dopamine tract in the median forebrain bundle which is lesioned

60. Say something about the precursor(s) of the transmitter(s) that affect the cannabis receptor.

phosphatidylethanolamine and phosphatidylinositol are membrane phospholipids

61. Why would a physician prescribe neostigmine?

to make up for the low acetylcholine in patients with myasthenia gravis

63. What transmitter receptor binds the tranquillizers Valium and Librium and also the hypnotics Barbiturates?


64. Why would a drug derived from the deadly nighthsade be used as a cosmetic?

atropine dilates the pupils and makes for a beautiful woman (belladonna)

65. There are two prodicts of the enzyme PLC (phospholipase C). ANSWER FOR EITHER PRODUCT What is next step in the cascade after tie product?

ip3 affects its receptor, a calciou channel in the er, dag activates pkc

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This page was last updated 2/16/2015