1. How are lysosomes involved in turnover in the cell?

they are little containers of hydrolases that merge with endosomes and phagosomes

2. What does aspirin do that makes us refer to it as an antipyretic?

it reduces fever caused by pyrogens

3. What molecule, the product of transcription, exits through the nuclear pores and resides on the ribosomes for the sake of translation?

mRNA

4. What is there too little of in a person with goiter?

the answer could be iodine, thyroxin, T3 or T4

5. Why was a red blood cell especially useful in showing there are two layers of phospholipids in a cell membrane.

only one membrane (plasmalemma), flat like a coin, easily obtained, easily counted

6. We speak of membranes as having the property of high resistance. What is the term related to resistance that is more analogous to permeability (e.g. whether the membrane does or does not have permeability to sodium ions)?

conductance

7. At the beginning of the axon (axon hillock), the voltage generated by a depolarization at a synapse in that cell might be very small. Give a possible reason.

there is decay as it spreads from synapse to hillock, perhaps there was a simultaneous IPSP

8. In the equivalent circuit of the Goldman equation, why is the chloride battery in reverse polarity relative to the sodium battery when, in fact, the chemical gradients are in the same direction?

chloride is an anion while sodium is a cation

9. The voltage gated sodium channel of the action potential is activated by depolarization caused by a spike upstream on the axon. How come the spike does not activate the sodium channels behind it?

they are inactivated, there is a refractory period

10. Discussing the passive propagation of voltage along an axon, the current down the axon was shown. Why did this current become smaller and smaller the further away form the site where you injected current?

current leaks out through the axon membrane's resistance and capacitance

11. Say something about why polio has not been eliminated worldwide.

mostly politics, groups who think western medicine is a plot, also there are a few people who maintain an infection

12. What happens to the permeability of the postsynaptic membrane to monovalent ions during an IPSP?

permeability to both potassium and chloride is increased

13. Some neurotransmitter receptors are channels. What kind of molecule is the other type of neurotransmitter receptor?

g protein coupled receptor

14. "The alpha subunit of the heterotrimeric G protein activates adenylyl (adenylate) cyclase." What reaction does this enzyme catalyze?

starting with ATP, it makes cAMP

15. Unfortunate for the victims but fortuitous for researchers, a bad batch of heroin contributed to research in Parkinson's disease. How?

there was an impurity called MPTP which has since been used to study animal models

16. How does the autonomic nervous system relate to a body-builder's knowledge that (s)he will look more muscular after getting "pumped?"

hyperemia (increased blood flow) makes the muscles bigger

17. Why would atropine be a useful drug in the treatment of diarrhea?

it would block motility in the gut

18. "Viagra potentiates the action of nitric oxide." How?

the NO signal pathway increases cGMP, and Viagra blocks its phosphodiesterase

19. At 150% of the resting length, a muscle can generate only 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

20. In muscle contraction, "Power stroke causes filaments to slide; ADP is released." ADP is released from what molecule?

myosin

21. What is glycogenolysis?

production of glucose from glycogen

22. How is the calcium channel in the sarcoplasmic reticulum opened?

by the calcium channel spike in the transverse tubule

23. Percent of the hemoglobin that is saturated with oxygen is graphed as a function of (what) in the oxyhemoglobin dissociation curve?

partial pressure of oxygen in mmHg

24. Why is a molecule such as glucose referred to as a carbohydrate?

the chemical formula is Cn(H2O)n

25. Describe where nitrogen is in an amino acid and how this chemistry is changed when that amino acid is linked to the acid group in another amino acid.

an NH2 sticks out of the central carbon, and, in forming a peptide bond, it is NH-bond

26. The birth control pill can be taken orally. Why, in contrast, is it necessary to inject insulin?

a protein would be broken to individual amino acids in digestion

27. For GLUT-4, ANSWER EITHER (1) Name one of the three tissues in the body where this transporter is active. OR (2) What hormone increases the level of this transporter in the plasmalemma (cell membrane)?

1-muscle, liver, adipose tissue; 2-insulin

28. If you have a family history of Type 2 diabetes, what aspect of your wellness would you want to be especially vigilant about?

your weight (maybe smoking too)

29. For glucagon, ANSWER EITHER (1) What kind of molecule is its membrane receptor? (2) What would it do at the level of the adipose cell's membrane?

1-G-protein coupled receptor, 2-release of free fatty acids

30. Say something about the status of the tricuspid and bicuspid valves during diastole that relates to the point "Atrial contraction contributes only a small fraction of the vertricular filling."

they are open

31. In the context of types of blood vessels, ANSWER EITHER (1) What is the type of blood vessel that regulates blood flow to various vascular beds? (2) What aspect of this blood vessel type does the regulation? OR (3) What portion of the nervous system regulates these blood vessels?

1-arteriole, 2-smooth muscle, 3-sympathetic

32. Why doesn't blood start flowing into the aorta when the ventricle begins to contract?

ventricular pressure is initially lower than diastolic arterial pressure

33. What is the mechanism by which aspirin might prevent a heart attack?

it is an anticoagulant

34. What does a defibrillator do resuscitate a patient?

it starts the SA node

35. Why wouldn't aspirin or ibuprophen help to relieve inflammation of the bronchi?

not caused by prostaglandins, caused by leukotrienes

36. Why does only 350 ml of gas exchange in a tidal breath of 500 ml?

dead space of trachea and bronchi

37. Let's assume that none of us have cystic fibrosis. What is the status of your cystic fibrosis transmembrane regulator?

it is normal

38. At rest, the partial pressure of oxygen in your veins is 40 mm Hg. At that level, approximately what percentage of hemoglobin is still saturated with oxygen?

75%

39. In addition to hemoglobin, another protein is important in red blood cells, an enzyme. ANSWER EITHER (1) What is this enzyme called? OR (2) What reaction does it catalyze?

1-carbonic anhydrase, water and carbon dioxide into carbonic acid

40. For gout, ANSWER EITHER (1) What chemical is there too much of? OR (2) Name a drug that might be used in treatment.

1-uric acid, 2-NSAIDS for inflammation or allopurinol to inhibit the enzyme

41. In addition to a facilitated glucose transporter on the basolateral surface of a cell in the proximal convoluted tubule, name ONE of the two other transporters (AND say where) necessary for recovering glucose from the primary urine.

sodium-glucose transporter on the apical surface, sodium pump on the basolateral surface

42. Aquaporins ANSWER EITHER (1) Which part of the nephron has aquaporins when they are needed? OR (2) Why is there already a handy gradient to drive recovery of water into the interstitial fluid?

1-collecting duct, 2-the interstitial fluid is hypertonic

43. What would an ACE inhibiting drug (angiotensin converting enzyme inhibitor) be used for?

decrease hypertension

44. "If you were the creator, you might package digestive enzymes in an inactive form so the cells that make the enzyme (precursors) don't digest themselves; it makes sense." ANSWER EITHER (1) What is the general name of the precursor enzyme granule? OR (2) Give a name of ONE enzyme precursor

1-zymogen, 2-trypsinogen, chymotrypsinogen, procarboxypepidase, others.

45. Say something about lactose intolerance.

lactose is broken in half by a lactase that is missing in some adults (not infants), more likely not of northern European origin, the undigested lactose nourishes some bacteria that contribute to indigestion

46. Why does your skin turn yellow if you have hepatitis?

inflammation in the liver causes urobilinogen to spill into the blood stream

47. Where are the cell bodies of the axon terminals in the posterior pituitary that release antidiruetic hormone?

hypothalamus (paraventricular and supraoptic nuclei)

48. In Addison's disease, there are insufficient livels of glucocorticoids. Therefore, on the basis of homeostasis, there is too much of what trophic hormone from the pituitary?

ACTH

49. Say what is abnormal in people, EITHER adults OR infants, if there is EITHER too much OR too little thyroxine (pick one).

too much adult hyperthyroid too energized, too little adult hypothyroid sluggish, too little infant cretinism challenged

50. Why would some exposure to sunlight be good for your calcium homeostasis?

sunlight triggers the first of several steps in converting vitamin D to its active form, and Vitamin D stimulates intestinal absorption of calcium and phosphate

51. "T4 would affect gene transcription by acting on an upstream response element." Not exactly. Say something else about how thyroxine affects gene transcription.

gets converted to T3, acts via a receptor and in concert with a paired retinoic acid receptor that binds retinoic acid and an adjacent response element

52. Why is Tamoxifen referred to as a SERM (selective estrogen receptor modulator)?

once considered an estrogen antagonist, it is actually an agonist in bone and uterus (while it is an antagonist in breast)

53. Why did it seem, in the days before they found adverse effects, that COX-2 inhibitors would be better than NSAIDS like aspirin and ibuprophen?

they inhibit both COX 1 & 2 and, because of this, have adverse affects in the stomach and don't target arthritis as selectively

54. Suppose you had a male animal with a reproductive cycle that was seasonal. How would you do a lab study to see if the size of the testes is different in different seasons?

raise some on 8 hr light - 16 hr dark, the others on 16-8

55. Pluripotency ANSWER EITHER (1) What does that mean? OR (2) Cells from what portion of the blastocyst have this property?

1-these cells can differentiate into any adult cell type, 2. inner cell mass

56. When an imbalance of a small chromosome (trisomy-21, Downs syndrome) has a huge effect on the child, how is it possible that women have two X chromosomes while men have one, without resulting in an intolerable difference in the dosage of X chromosomal genes?

one X is inactivated in every cell in the woman

57. "So you see, the female developmental pathway is the default pathway while the male pathway is the active pathway." Say something about chemicals or embryonic ducts that lead to this generalized statement.

paramesonephric duct that would become uterus and tube degenerates with MIF from testes and mesonephric duct turns int epididymus, vas deferens and ejaculatory ducts under the influence of testosterone from the testes

58. Even when capillaries are not damaged by the injury that fills the area outside the capillary with bacteria, neutrophils migrate to where they are needed. ANSWER EITHER (1) What is this migration called? OR (2) How, when the capillary is intact, did this polymorphonuclear granulocyte get there?

1-extravasation, 2-slither out between endothelial cells

59. Why and under what circumstances would you administer antibodies (for passive immunity) to an Rh negative woman?

if she gave birth to an Rh+ baby so she would not develop active immunity and not be able to safely get pregnant again

60. An antibody interacts with an antigen. ANSWER EITHER (1) Say something about what part of the antigen one antibody molecule binds to. OR (2) Say something about what part of the antibody molecule binds to the antigen.

1. an epitope (antigenic determinant), 5 - 15 amino acids long, 2-the tip of the Y short- and long-chains, the variable region

61. A B cell develops into a plasma cell that puts out an antibody received by a receptor on a mast cell. ANSWER EITHER (1) What category (type) of antibody is this? OR (2) What is secreted from this mast cell when it binds an allergen?

1-IgE, 2-histamine

62. The somatosensory cortex. That's a functional name. Give the anatomical name.

postcentral gyrus

63. Spinothalamic system. ANSWER EITHER (1) Where is the tract in the spinal cord? (2) Which side of the spinal cord is it in (relative to where the receptor is)? OR (3) What is the function of this submodality?

1-anteriolateral, 2-other side (contralateral), 3-pain and temperature

64. "In conclusion, Parkinson's and Huntington's diseases are functionally opposites in a homeostatic feedback to the site where voluntary motor movements are initiated." ANSWER EITHER (1) What is this site where voluntary motor movements are initiated? OR (2) What brain structure is on the pathway from the globus pallidus (in the basal ganglia) to this site where voluntary motor movements are initiated?

1-precentral gyrus, 2-thalamus

65. In the projection to the brain for the sense of taste, name a place after the first synapse in the medulla.

thalamus, post-central gyrus

66. "In the projection, Olfaction does not go to some place in the cerebral cortex." Tell me one of the places the olfactory bulb projects to.

hypothalamus, hippocampus, amygdala, cingulate (limbic system)

67. The organ of Corti (spiral organ) lies on the basilar membrane and is right next to the tectorial membrane. Describe how the tectorial membrane assists in auditory transduction.

stereocilia are bent as vibrations move hair cells relative to the tectorial membrane

68. Why did Bekesy need to conjure lateral inhibition to reconcile his data with Helmholtz's place theory?

the localization (data) was too crude to explain that a person can hear the difference of just a few Hz

69. Why couldn't you see the ultraviolet light I showed you?

the lens blocks the uv

70. Progressive myopia can be attributed to what change in the shape of the eyeball?

it gets longer front to back

71. "Macular pigments protect foveal cones from... ANSWER EITHER (1) Protect foveal cones from what? (2) What kind of molecules make up the macular pigments?

1-blue light, 2-carotenoids (lutein and zeaxanthin)

72. Glaucoma ANSWER EITHER (1) What goes wrong in the aqueous humor? OR (2) Why would you go blind if it were not treated?

1-pressure builds up, retinal ganglion cells die

73. The occulomotor nerve, the third cranial nerve ANSWER EITHER (1) Does what to the pupil...? OR (2) ...under what lighting conditions?

1-constricts it, 2-in bright light

74. Why does the rod's cation channel close in the light?

cGMP PDE has broken cGMP down to GMP, and it was cGMP that gated the channel

75. Retinal pigment epithelial cells from elderly donors are full of lipofuscin that fluoresces yellow to short wavelength excitation. This accumulation relates to what function of the retinal pigment epithelial cells?

phagocytosis of rod debris

Return to syllabus

Return to Stark home page

last revised 12/5/2013