1. In the 1800's, Broca delineated a brain area critical for speech. How did he do this?

after death, on autopsy, he saw brain damage in a patient with damage to his speech

2. In the knee-jerk reflex, ANSWER EITHER (1) Where is the cell body of the motor neuron? or (2) Where is the cell body of the sensory neuron?

ventral horn in gray matter of spinal cord, in dorsal root ganglion PNS

3. "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"

4. If a thrombus occluded one internal carotid artery, the brain damage might not be immediately devastating because of what anatomical specialization

circle of Willis

5. In explaining fluorescence, why is the emission a longer wavelength than the excitation?

energy is lost before a photon is re-emitted

6. A figure was shown to you where axons looked red because of labeling of tau. ANSWER EITHER (1) Say something about the technique that allowed you to see tau. (2) Say something about the function of tau. OR (3) In what neurological disorder does tau accumulate?

antibody & confocal, microtubular binding protein, Alzheimer's

7. A specialized brain scan technique shows a defect in a pathway in blind subjects. What lobe does this tract go to?

occipital

8. 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

9. Something more than the endothelial cell is proposed to be responsible for the blood-brain-barrier that makes the cerebro-spinal-fluid a privileged compartment. What is the additional cell type?

astrocyte (glial cells)

10. Why, in the transmission electron microscope, does myelin look so dark?

membranes bind osmium (and it is electron dense) and myelin has many layers of membrane

11. The concept of the motor unit, all the muscle cells innervated by one spinal motor neuron, was introduced. How is that muscle unit related to Halstead's proposal on how he had some recovery after polio then the symptoms recurred later in life?

new muscle cells were recruited to units innervated by surviving neurons, but, by middle age, these new sprouts are lost

12. "Multiple sclerosis is an autoimmune disease." ANSWER EITHER (1) To what protein? OR (2) How can you get immune to a protein that belongs in your body?

myelin basic protein, its sequestration from immune surveillance has been compromised

13. When Jim (JH), our subject with CMT (the peripheral neuropathy) showed us how small his calves are, he made an analogy to what demyelinating disease?

polio

14. Why does Jim see his podiatrist regularly and rub cream on his feet daily?

he might get a sore, and he might not feel it, and it might get infected

15. "Thimerosal was removed from childhood vaccines in 1999." ANSWER EITHER (1) What is thimerosal? OR (2) This argues against thimerosal being a cause of (what disorder?).

a mercury-containing preservative, autism

16. When a square wave of current is injected into the cell, the Voltage change is gradual because of (what property of the membrane?).

capacitance

17. A large enough square wave injection of current depolarizes the axon to the threshold of the action potential. What do you call the voltage response to an injection in the other direction across the membrane?

hyperpolarization

18. You are using Neher and Sachmann's patch clamp technique. The X-axis of your record is time. What is on the Y-axis?

current

19. Ouabain is applied to the cell. ANSWER EITHER (1) Why does the membrane potential change by a few mV? OR (2) Why doesn't the membrane potential go away right away?

3 sodiums to 2 potassiums make the pump electrogenic, otherwise potentials are based on huge reservoirs of ion gradients that would run down very slowly if the pump were blocked

20. "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?

conductance

21. Why is the Voltage calculated by the Nernst equation referred to as the equilibrium potential?

equilibrium was assumed in the derivation of the Nernst equation

22. In the Goldman equation, concentrations (in and out) of sodium, potassium and chloride, and permeabilities for all three ions, are shown. There is an equivalent circuit (with electrical components) for the Goldman equation. What is used in the circuit model for the sodium permeability? Be thorough enough in your answer to address what happens to sodium permeability during the action potential.

a variable resistor (potentiometer) that lets sodium permeability go up

23. "Cole and Curtis's bridge went out of balance." What did we learn from their 1939 work on the squid giant axon with the Wheatstone bridge?

conductance goes up as the action potential passes

24. You remove both adrenal glands of a rat and let it recover. ANSWER EITHER (1) What is different about the animal's specific appetite? OR (2) This is explained by the absence of what hormone?

craves salt (NaCl) b/c of loss of aldosterone

25. Discussing passive spread of a decremental potential, the current spreading down the axoplasm gets smaller with distance from a place where a stimulus is applied. What happened to the current that was no longer going down the axoplasm?

it leaked through the axon membrane's resistance and capacitance

26. The lecture and figures refer to a sodium channel that is about to be depolarized to threshold by an upstream action potential as "closed." Right after the action potential has passed, what term do we use to describe the status of the sodium channel?

inactivated

27. What happened to the early current in Hodgkin and Huxley's "I-V curve" when they replaced 460 mM NaCl with choline chloride.

the inward current was abolished

28. Why was Electrophorus electricus useful in channel research?

sodium channels were so plentiful in the electric organ that they could be isolated and characterized

29. At one time they thought that the positively charged amino acids in S4 lined the channel, but eventually they agreed that S4 did (what?)?

sensed the voltage for gating to cause a conformational change for activation

30. Parathormone, calcitonin, and (what other hormone?) help to maintain appropriate levels of blood Ca2+?

vitamin D

31. Why would pheochromocytoma (PC) cells be a reasonable model for studying neurotransmitter release?

can culture adrenal medulla cancer cells which release catecholamines

32. For gap junctions, ANSWER EITHER (1) What is the relative (or absolute) conductance? (2) What is the distance between the cells, relative to the distance outside the gap junction patch? OR (3) What is the word used for the multimer of proteins (or for each molecule) that makes up the channel?

high 120 pS, small 3.5 vs 20 nm, connexon, connexin

33. "There are no inhibitory neuromuscular junctions in the vertebrate." What does that information tell us about "the final common pathway in the integrative action of the nervous system?"

it must be in the spinal motor neuron since there is no integration after that

34. 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

35. In Sir Bernard Katz's Nobel Prize-winning research, he turned end plate potentials into 0, 1, 2, or 3 miniature end plate potentials. ANSWER EITHER (1) How? OR (2) Why?

by decreasing calcium ions, to show that vesicles were the unit of synaptic transmission

36. Describe either the freeze-fracture or the transmission electron microscope image of a vesicle in the process of release.

holes (pits), omega figures

37. Why would there be transporter molecules in the vesicle membrane?

to concentrate the neurotransmitter

38. "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

39. The shibire mutant of Drosophila ANSWER EITHER (1) What protein is altered? (2) Why was it a temperature sensitive mutant that was studied? (3) What is the behavioral phenotype? OR (4) What cellular process is altered?

dynamin, paralysis would be lethal, paralysis, conversion of coated pit to coated vesicle

40. For a deep, dirty puncture wound in the finger, ANSWER EITHER (1) Why would you want to try to make it bleed? (2) What would you want to look into when you hurry off to your family doctor?

"wash" the anaerobic bacterium out, have you had your tetanus booster in the last 10 yrs

41. What is meant by the term "putative neurotransmitter?"

it is probably a neurotransmitter but it is not proven to everyone's satisfaction

42. "Vasoactive intestinal peptide might be found in the brain." What the heck?

even though it might have nervous system function, it retains the name based on its original characterization

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

pomc

44. There are channel receptors and they are called ionotropic. There are G protein-coupled receptors that are called (what?).

metabotropic

45. Blocking the muscarinic cholinergic receptor on the heart with atropine would save your life if you were poisoned with what class of molecules?

acetylcholinesterase inhibitors

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

l-DOPA is a common precursor of melanin and dopamine

47. One portion is called cranio-sacral. What is the equivalent name for the other portion (of the autonomic nervous system)?

thoraco-lumbar

48. How is a norepinephrine breakdown enzyme an important target in the pharmacology of treatment for depression?

norepinephrine is obviously an "upper", so potentiating its action by inhibiting its breakdown would certainly be uplifting

49. Nitric oxide (NO) had previously been called "endothelial derived relaxation factor." What was relaxed?

smooth muscle in arterioles of the corpus cavernosum

50. "Now that there are antidepressants, there is no reason to be depressed." Then why is there so much controversy about drugs like Prozac (and Paxil and Zoloft)?

some critics implicate them in increased risk of suicide or homicide

51. Give one of the two possible reasons a diet high in tryptophan might make you sleepy.

precursor to serotonin and to melatonin

52. 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

53. What would happen to most of the l-DOPA given to a Parkinson's patient?

it would get decarboxylated before it crossed the blood brain barrier

54. "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

55. Receptor antagonists for what transmitter are considered to be the most effective treatment of schizophrenia?

"Tritiated naloxone binds to places in the brain and is displaced by (what?) in parallel with their strength."

opiates

56. Pick EITHER phosphatidylethanolamine OR phosphatidylinositol and relate it to marajuana.

both phospholipids are precursors of the endogenous cannabinoid, anandamine or 2-AG respectively

57. What is in the tail of Torpedo that made it useful for cloners interested in the nervous system?

lots of tissue with acetylcholine receptors

58. What is in the tail of Torpedo that made it useful for cloners interested in the nervous system?

lots of nicotinic acetylcholine receptors

59. What may alleviate the weakness of myasthenia gravis?

neostigmine

60. Why do you need to be very careful when you use muscle relaxation in conjunction with anesthesia?

while it is important for your patient or your research animal not to move, you must not paralyse without blocking pain

61. There are not any channel receptors for (name ONE transmitter).

dopamine, norepinephrine

62. What receptor binds barbiturates? State what the natural transmitter is and whether it is ionotropic or metabotropic.

a GABA channel

63. ANSWER EITHER (1) The second and third cytoplasmic loops (and what terminal?) of the beta adrenergic receptor interact with the next downstream molecule in this cascade. OR (2)What is the next downstream molecule in this cascade?

c terminal, g protein

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. Why is caffeine an "upper?"

norepinephrine and epinephrine action is potentiated since the second messenger's breakdown by cAMP phosphodiesterase is inhibited

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revised 2/15/2016