1. For EITHER smooth endoplasmic reticulum or Golgi apparatus, say ONE function.
steroid synthesis, detoxifying (liver microsomal fraction), calcium ion
2. In an equivalent circuit of the axon membrane, in ADDITION to batteries
and resistors, what other component is found (hint, the component that changes
voltage as a function of time).
3. What affect does cortisol have on the anterior pituitary gland?
negative feedback, inhibit ACTH release
4. "Cells of an exocrine gland release their product into a duct."
Where do cells of an endocrine gland release their product?
the blood stream (capillaries)
5. "The capillary beds in the hypothalamus and anterior pituitary are
'wired' together in series; there are similar systems in the kidney and
connecting the intestine with the liver." What is the term used for
this kind of blood vessel or system?
6. Thyroid gland (answer either) (1) Who would have an enlarged thyroid
gland? OR (2) What is that enlarged thyroid gland called?
someone deficient in dietary iodine, goiter
7. For rhodopsin, what is it that turns the otherwise colorless protein
into a pigment?
retinaldehyde, the aldehyde of vitamin A is the chromophore
8. "You can see two sides of the membrane in transmission electron
microscopy and you can see membrane proteins with the freeze fracture technique."
Well, that's obviously an oversimplification. What is it that actually creates
the electron density?
heavy metal, osmium, platinum, lead, uranium
9. Say one of the things that needed to be done to make phospholipids show
up on an audioradiogram of a thin layer chromatography plate.
label them with radioactive phosphate, expose film
10. In terms of the biochemical constituents of the cell membrane, answer
either (1) Why do membranes have high resistance? or (2) Despite the high
resistance, why is there at least some conductance across the membrane?
hydrophobic interior fatty acids, channels
11. Describe the trick to record the electrical current from a single nicotinic
put a patch clamp electrode up against the channel
12. What membrane protein uses energy derived from ATP to move sodium and
potassium ions across the cell membrane?
sodium pump = sodium potassium pump = Na+K+ATPase
13. "At the axon hillock (the beginning of the axon), there is a decision
as to whether there is enough net excitation to fire off an action potential."
If there were an excitatory graded potential at the dendrite, why might
there not be enough net excitation at the hillock?
maybe there was also an IPSP, also EPSP spreads decrementally
14. 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
15. Although it is close to the truth, and very useful in the derivation
of the Nernst equation, in what way was the equilibrium assumption not completely
ions do flow down their concentration gradient when the channel is open
even though electrical potential should be equal and opposite to chemical
16. In the equivalent circuit of the Goldman equation, why are the chloride
vs sodium batteries in reverse polarity even though their ion gradient is
the same (high outside, low inside)?
because sodium is a cation and chloride is an anion
17. "You can't have more current flowing into one place than flows
out of that place," is my casual wording of one of (whose?) laws that
applies to circuits.
18. An axon goes past a cell body, called a pseudounipolar neuron. That
cell body is located in the dorsal root ganglion near the spinal cord. In
the knee-jerk reflex, answer ONE of the following: (1) What kind of information
is carried in this axon? OR (2) What does this nerve cell connect to?
stretch of muscle, spinal motor neuron
19. In the peripheral nervous system, the action potential... (answer either)
(1) jumps from one (fill in the blank) to the next OR (2) in other words,
it jumps past (what?).
node of Ranvier, Schwann cell = patch of myelin
20. "Each spinal motor neuron connects to a whole bunch of muscle cells
called a motor unit." In Halstead's paper on post-polio syndrome, how
is this connectivity affected (answer either) (1) during recovery after
polio strikes, OR (2) later in life when symptoms get bad again?
1-more muscle cells per muscle unit supported by surviving axons, 2 extra
sprouts are lost
21. Why did Sherrington use the word "final" when he referred
to the spinal motor neuron as the "final common pathway in the integrative
action of the nervous system?"
since yhe motor end plate only has excitation, there can be no integration
further out (at the neuro-muscular junction)
22. How did calcium ions become available to bind to the synaptic vesicle
they came in through the voltage gated calcium channel at the terminal upon
arrival of the action potential
23. "Vagus-stuff slows the heart." Answer one of the following.
(1) What major subdivision of the autonomic nervous system does vagus-stuff
come from? (2) What chemical is vagus-stuff?
24. Why is it NOT correct to refer to acetylcholine as an agonist or an
those terms are for drugs, not the real transmitter
25. Why would you die if your acetylcholinesterase were inhibited?
too much acetylcholine would stop the heart
26. Vesicle membrane is retrieved. Answer either (1) What is this process,
cell drinking, called? OR (2) What do these pits that pinch off to vesicles
look like in the electron microscope?
pinocytosis or endocytosis, they are called "coated" because a
fuzzy coat of clathrin is electron dense
27. Norepinephrine is a neurotransmitter, and it is, chemically, an amine.
In it's biosynthetic pathway, name one of the precursors or one of the enzymes.
tyrosine tyrosine hydroxylase l-DOPA dopa decarboxylase dopamine dopamine
28. In contrast with the mechanism to terminate cholinergic transmission
(involving acetylcholinesterase) what keeps norepinephrine or epinephrine
from stimulating the receptor forever?
29. "Caffeine potentiates the 'upper' action of epinephrine and norepinephrine
by..." answer either (1) inhibiting the breakdown of what molecule?
OR (2) inhibiting what enzyme?
30. Some cranial nerves are part of the autonomic nervous system. Which
subdivision of the autonomic nervous system?
31. There are acetylcholine receptors that are channels. In addition, there
are acetylcholine receptors that are G protein-coupled receptors that are
called (what?), named on the basis of pharmacology.
32. For both branches of the autonomic nervous system, an axon exits the
central nervous system and makes a synapse in a ganglion. What is the receptor
for the neurotransmitter in the ganglion?
33. Why would an alpha-1 adrenergic agonist be useful as a nasal decongestant?
34. Why is a muscle weaker when it is fully extended than when it is shorter?
less overlap of actin and myosin
35. ATP binds to what muscle protein?
36. Reducing calcium ions in the extracellular fluid bathing the neuromuscular
junction would do (what?) to the vesicle release?
decrease (to 0, 1, or 2 per nerve impulse)
37. For myasthenia gravis, answer either (1) Why do the patients experience
muscular weakness? OR (2) What would be given to help the patient?
to few nicotinic channels, neostigmine (acetylcholinesterase inhibitor)
38. A channel to what ion mediates the action potential of the T tubules?
39. Say something (else) about the properties of the type of muscle fiber
that is sometimes called fast twitch.
white meat, anaerobic, strong but not enduring
40. What is the difference in stimulation that makes the force bumpy in
incomplete tetanus (as opposed to complete tetanus)?
incomplete -> complete as the frequency of nerve stimulations goes up
41. Give a source of muscle energy other than glucose and glycogen.
fat, fatty acids
42. MLCK (myosin light chain kinase) [answer either] (1) does what to myosin
light chain? OR (2) functions in what kind of muscle? OR (3) functions to
activate what process?
phosphorylates it, cross bridge activation, contraction
43. There is an axon terminal that releases acetylcholine at the neuromuscular
junction. By contrast, what is the geometry of neurotransmitter release
from the postganglionic neuron in the autonomic nervous system as smooth
muscle is activated or inactivated?
varicosities like beads on a string
44. What is so special about carbon that makes it the common denominator
of all organic molecules?
it makes 4 bonds
45. What molecule (or what kind of molecule) is the precursor of prostaglandins,
mediators of inflammation?
arachidonic acid, a polyunsaturated fatty acid
46. Urea is created (answer either) (1) to get rid of what waste? Which
is created because (2) what kind of molecule is being used by catabolism
ammonia (nitrogen), amino acids
47. Answer either: (1) Under what circumstances do you create lactic acid
to regenerate NAD? or (2) What is the immediate precursor from which lactic
acid is made?
when aerobic metabolism is not sufficient, pyruvic acid
48. By activation of the beta adrenergic receptor in the liver cell, adenylate
cyclase must chop (what? and how much?) off of ATP as cAMP is made.
49. Energy is ultimately needed when sodium ions "drive" a co-transporter
for glucose, but not by this transporter molecule. Where is energy used?
by the sodium pump
50. "The third phosphate of ATP is is not just broken off as inorganic
phosphate, but is actually delivered to a molecule." Regarding the
action of the insulin receptor, what molecule acquires phosphate from ATP?
the receptor is phosphorylated at a tyrosine residue (then other cascade
return to syllabus
return to stark home page