1. Relate "goose bumps" with temperature regulation in a mammal that has fur.

piloerection would fluff up the fur to conserve heat, goose bumps just show the smooth muscle poking up the "vestigial" hairs

2. Used as an example of homeostasis, thyroxine was shown to have what effect on the anterior pituitary?

"inhibits responsiveness to TRH" translates to: feeds back to decrease release of TSH

3. "Insensible" is a term applied to water loss by perspiration or panting in contrast with the water loss by micturition. What does "insensible" mean?

you're not aware of it

4. Why do you need a chromophore (such as retinal for rhodopsin and heme for hemoglobin) to make a protein into a pigment?

proteins do not absorb visible light

5. What must be true about the amino acids of the alpha helix of rhodopsin that would let it cross the membrane?

they would be hydrophobic

6. In addition to the receptor, in receptor-mediated endocytosis, what famous protein is seen in transmission electron micrographs that gives coated pits and coated vesicles their names?

clathrin

7. Reminder: The Goldman equation looks like the Nernst equation except that it includes concentrations (in and out) plus permeabilities for all three ions - Na+, K+ and Cl-. Only one of these 9 values changes at the beginning of the action potential. Which?

permeability for Na+

8. Write an equation obeying Ohm's law relating voltage and current but using conductance rather than resistance.

if E=IR (Ohm's law), then E=(1/g)I, so I=GE

9. What property keeps the action potential from triggering an action potential behind it as it travels down the axon?

refractory period

10. "Exponential" is the term describing Voltage as a function of time for charging or discharging a capacitor in an RC circuit. Draw this graph (for charging or discharging or both) where V is the battery's Voltage.

charging - goes up quickly then slowly, leveling off to V; discharging - goes down quickly from V then leveling

11. In saltatory (leaping) conduction, the action potential jumps from where to where?

one node of Ranvier to the next

12. What is the molecular mechanism for channel inactivation?

a stopper formed by amino acids near the n-terminus plugs the channel

13. What is different about the space constant vs the time constant for the passive propagation that explains why giant axons are fast?

space constant varies with square root of radius, time constant does not

14. Although Ramon y Cajal used Golgi's technique, and the two shared the Nobel Prize in 1906, only Ramon y Cajal's viewpoint required the existence of synaptic connections such as Nobelist Sherrington proposed. In what way did Ramon y Cajal's vs Golgi's viewpoints differ regarding this issue?

only Ramon y Cajal thought cells were separate entities that would need to signal to each other

15. What does a kinase do to a protein?

phosphorylates it

16. Conductance to what anion increases when the postsynaptic membrane hyperpolarizes?

Cl- is the biologically important anion

17. What neurotransmitter does the substantia nigra make for the control of motor movements?

dopamine

18. What binds to adenylate cyclase to activate so that it makes cAMP out of ATP?

alpha subunit of heterotrimeric G protein

19. Identify one of the two parts of the central nervous system where the parasympathetic output originates. Be specific.

brain (for cranial nerves) and sacral part of the spinal cord

20. What is the interesting parallel in the actions of Viagra and caffeine?

they both inhibit a phosphodiesterase, Viagra inhibits cGMP breakdown and caffeine inhibits cAMP breakdown

21. What prevents the myosin head from binding actin in striated muscle when a contraction is not called for?

tropomyosin

22. Bernard Katz won a Nobel prize demonstrating that the "quantum" of neurotransmission at the motor end plate is the vesicle. He made it so that one action potential (in the spinal motor neuron) would release 0, 1, 2, or 3 vesicles. How did he achieve this reduction?

by reducing the calcium ions that come in to mediate vesicle release

23. What enzyme is deficient in familial cases of Lou Gehrig's disease?

super oxide dismutase

24. While fasting, what does the liver do with the glycogen it stores?

breaks it to glucose and sends that to the blood stream

25. How does fat feed into metabolism to render ATP? (An answer for either type of components that make up a fat will be OK.)

glycerol gets converted to the precursor of pyruvic acid. Fatty acids get chopped down 2 carbons at a time to become acetyl CoA

26. "Tyrosine kinase" - where did the phosphate come from?

ATP donates the phosphate there (and pretty much everywhere)

27. What is released from adipose tissue under the influence of glucagon?

fatty acids

28. Insulin is made from a prohormone. State one of the things that are done to make insulin from this prohormone.

a peptide fragment is removed from between the 2 that are part of insulin and these are linked by 2 disulfide bonds

29. By what molecular mechanism does cAMP activate protein kinase A (A-kinase)?

2 cAMPs each bind 2 inhibitory subunits to activate 2 catalytic subunits

30. What are the cells that line blood vessels including capillaries called?

endothelial cells

31. What kind of blood vessels have the highest TOTAL cross sectional area?

capillaries

32. Taking blood pressure, you inflate the cuff to 180 mm Hg, then lower it. You hear nothing until the systolic pressure is reached. After the diastolic pressure is passed, you hear nothing. Why do you get sounds only between systolic and diastolic pressures?

turbulent

33. You feel chest pain so you take nitroglycerine. How did this save you from a heart attack?

relaxation of smooth muscle in coronary arteries would alleviate the block (that likely resulted from a thrombus or an embolism in an artery already partially occluded from atherosclerosis)

34. Why would you die of if there were too much time between heart failure and defibrillation without CPR (cardio-pulmonary resuscitation)?

brain would die without O2 (and glucose)

35. What is the biological word for the Adam's apple?

larynx

36. An asthma spray would contain an agonist for what naturally occurring neurotransmitter?

norepinephrine

37. "Water's surface tension would tend to collapse (close) alveoli." Answer either (1) How does physiology take care of this problem? or (2) People with what condition have a real problem because of this?

surfactant, premature babies

38. What is the intrapleural pressure? (I want an approximate value.)

slightly less than atmospheric

39. In the intestine and the kidney tubule, three processes are needed for glucose transport, (1) basolateral sodium pump, (2) basolateral facilitated diffusion, and (3) apical... [your turn].

glucose/sodium cotransporter

40. Instead of injecting inulin, what test is there for clearance assaying for a substance already in the body?

creatinine

41. By what molecular mechanism would ADH (antidiuretic hormone) make the collecting duct recover water better?

add aquaporins

42. When I was in first grade, we were told to keep a saltine cracker in our mouth and notice that eventually it tasted sweet. What enzyme is responsible for this?

amylase

43. The hepatic portal vein carries blood from the small intestine to where?

liver

44. Chief cells: answer EITHER (1) What is the name of the zymogen (precursor) in the granules of these cells. OR (2) Acid secreted (from what cell?) helps to form the active enzyme from the precursor?

pepsinogen, parietal

45. What is the hormone from the adrenal medulla?

epinephrine (adrenalin)

46. Gastrin stimulates secretions of parietal and chief cells. Name these secretions.

HCl, pepsinogen

47. What hormone would put calcium back into bones?

calcitonin

48. Why would your skin be dark if you had Addison's disease (inadequate cortisol, no feedback, too much ACTH)?

ACTH mimics melanocyte stimulating hormone

49. Would the corpus luteum build up and break down in women who are taking the pill? (Include in your answer why or why not.)

no b/c steroids of the pill inhibit FSH and LH which would build follicle into corpus luteum

50. What pituitary hormone maintains the cells that secrete testosterone?

LH

51. Vitamin D has effects more similar to (which?) calcitonin or parathormone. Explain (justify).

increase blood calcium like parathormone

52. Tamoxifen used to be called an antiestrogen but might now be better referred to as a SERM (selective estrogen receptor modulator). Why?

antagonist in some tissues but agonist in others

53. Non-steroidal antiinflammatory drugs (NSAIDs) block converrsion of what fatty acid to prostaglandins?

arachidonic

54. What close relative of retinal (retinene, the part of rhodopsin that absorbs light) is important in the activation of the hormone response element by triiodothyroxine?

retinoic acid

55. For purposes of family planning, some men elect to have a straightforward surgery that results in sterilization. What is done?

vasectomy = ligate and sever the vas deferens

56. Simultaneous with menstruation, what happens to the corpus luteum?

it regresses (becomes corpus albicans)

57. Testes, prostate, bulbourethral gland (Cowper's gland). What gland that is missing from that list contributes to semen?

seminal vesicle

58. What part of the blastocyst will eventually (much later) become the placenta?

trophoblast

59. Eosinophils are a type of polymorphonuclear granulocyte. What is eosin?

a histological stain


60. In what way do different antibodies create different risks for the fetus, comparing the ABO blood groups vs. Rh factor.

IgM not cross placenta but IgG does so 2nd Rh+ fetus is a problem for an Rh- mother unless she is given antibodies after the first is born

61. For inflammation, answer either (1) What are the three components of the triad? Or (2) What chemical mediator from mast cells contributes to inflammation?

warmth, redness, swelling, histamine

62. How can an infant be immune to some diseases between birth and weaning?

IgG across placenta, IgA in milk

63. Where is the cell body for the somatosensory receptor cell?

right outside the dorsal root of the spinal cord, dorsal root ganglion_

64. Why does a textbook have a lateral view of the cerebral cortex which has different locations colored differently?

to emphasize localization of function, for instance sensory areas for different modalities

65. WHY (note, I am just asking why) would a half spinal cord lesion affect senses mediated by spinothalamic vs lemniscal systems below the injury differently?

where they cross over is different, spinothalamic below the lesion, lemniscal above

66. The corticospinal tract would be involved in arm and leg movements. In what way is this situation different for the face?

cranial nerves

67. Contrast how cAMP gates a cation channel in an olfactory receptor cell with the way acetylcholine gates the nicotinic receptor.

cAMP from inside the cell, Ach from outside, both channels are ligand gated

68. For the fifth taste primary (other than sweet, sour, salt and bitter), what chemical(s) stimulate it?

glutamate, amino acids


69. The stapes drives vibrations to what structure?

oval window

70. "There is tonotopic localization in the auditory cortex." Explain.

different frequencies at different locations in an order

71. What happens to your vision when the ciliary muscle is contracted?

when ligaments become flaccid, the lens gets rounder, accommodating for near vision

72. Young and Helmholtz proposed a widely accepted theory of trichromatic color vision in humans. Answer either (1) what kind of cell, or (2) what kind of molecule has these three specific peak wavelengths of sensitivity?

cone, rhodopsin

73. What does activation of the parasympathetic portion of the occulomotor nerve do to the pupil?

closes

74. Say something about why the macula (the area around the fovea) looks yellow when viewed through an ophthalmoscope.

carotenoids zeaxanthin and lutein block blue light to protect foveal cones

75. Why is there lutein in your vitamin pill?

this is one of the carotenoids in the macular pigments that protect


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last updated 12/5/2017