W3006    Fall 2002         Physiology     Final Exam     NAME________________________________________

 1.  President Kennedy seemed to have the health and stamina of an accomplished athlete, playing touch football for reporters and showing off his almost constant suntan.  But when his medical records were recently made public, it became clear that he was, in fact, rather sickly. 

 Kennedy had Addison’s disease, also called adrenal insufficiency, in which the adrenal gland secretes much less hormone than normal.  The bronze color of his skin was not from the sun, but rather is a symptom of this disorder. 

A.  Explain why this disorder would lead to increased pigmentation in the skin.  Your answer should include the specific names of  a) the hormones involved, b) the anatomical structure where they’re produced, and c) the cells of the skin that are involved. (10 points total)  

B.  While a senator in his 30’s, Kennedy was operated on for back pain, and the surgeons were amazed to discover that his bones were as soft as those of an elderly person.  It seems that the corticosteroids he was taking caused him to develop severe osteoporosis. 

This might have happened because corticosteroids can affect the parathyroid gland.  What effect would they have and how would this lead to development of osteoporosis?  Your answer should include whether the hormones would increase or decrease, as well as the specific bone cells that would be involved, and what aspect of their function would be changed.  (8 points total)

C.  Another possible mechanism by which steroids lead to development of osteoporosis is that they have an effect on certain membrane proteins in kidney cells which contain calbindin.  Describe what effect the steroids would have that could lead to osteoporosis, and what calbindin is doing in these cells.  (6 points total)

D.  The recently released medical records show that during the Bay of Pigs and Cuban Missle Crisis, Kennedy was given increased doses of salt tablets, because the adrenal gland needs to be especially active in times of stress.  Which specific defect were the salt tablets intended to correct?  Your answer should indicate the hormone involved, and what its function is.  (6 points total) 

E.  If he had actually gone to Cuba at that time (a warm climate), he would have been told to increase his salt intake even  more.  Why?

 

F.   When women have Addison’s disease, they often lose hair in the pubic and axillary region, while men with the disease do not develop this symptom.  Why?

 

2.  In many elderly people, blood pressure changes within an hour after eating a meal.

 

A.  After eating a meal, more blood flows to the digestive tract as a result of  (more)  (fewer) action potentials traveling down (sympathetic)  (parasympathetic)  neurons to the blood vessels in this region.  These neurons secrete (norepinephrine)  (acetylcholine) that stimulates  (alpha)  (beta-1)  (beta-2) (nicotinic)  (muscarinic) receptors on the smooth muscle of the blood vessels.

 

C.  Since more blood is in the vessels near the digestive tract, there is less blood returning in to the heart in the veins.  What effect will this decrease in venous return have on blood pressure? List the formulas that you’ll need below, including abbreviations and what they stand for, then write an explanation below that.

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1.     (BP) Blood Pressure  =  

 

2.    

   

3.   

 

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Explain.

 

3.  The figure shows changes that occur in the circulatory system during light exercise, such as jogging, compared to the values at rest.  Considering the values given, which of the bars drawn (A, B or C) would you say represents the changes you’d expect to see in Resistance in the circulatory system? 

A.  Explain your answer.  Include a formula that helps you decide on the value.

  Sorry, don't have figure online, will see if I can get it there....

B.  Although EDV increases slightly, Stroke Volume increases to a much greater degree.  Based on this finding, would you say that the Frank-Starling effect is responsible for the large increase in stroke volume?

 

If yes, explain why you reached this answer.

If no, explain what you think is responsible for the increase in SV.

 

4.  Fill in with the name of the appropriate lipoprotein.

Over the epithelium and through the lacteals
To the blood vessels we go.
The _______ know the way to carry the lipids  (2)
Through white and slow-moving lymph.

This question was inspired by Lisa Kessler's poem:

Twas the Night Before Physio, and while in their beds,
Visions of blood vessels danced through their heads.
Sexual differentiation was explained with great care
In hopes that passing grades for all would be there!
Now Calcium! Now Scrotum!
Now Gastrin and Wolffian!
On Insulin! On Estrogen!
On Exocrine and Mullerian!
To the top of the class!
To the top of roll call!
Now pass that test, pass that test,
PASS THAT TEST ALL! 

4.         Candy is dandy
            But liquor is quicker.  

Ogden Nash was reflecting on how quickly people get friendly after ingesting sugar or alcohol, but his poem could also describe the speed at which these substances are absorbed into the blood stream.  Alcohol can diffuse directly through cell membranes, so it can be absorbed through the walls of the stomach, and thereby reach the blood more quickly than sugar, which must first reach the small intestine.  However, after having a drink of alcohol, most of the alcohol will actually be absorbed in the small intestine, not in the stomach. 
A. Explain why more alcohol is absorbed in the small intestine than in the stomach, based on the anatomical structure.  (4 points total)

B.  One way to decrease the effects of alcohol on the brain is to slow down its aborption.  Since most of the alcohol is absorbed in the intestines, its absorption will be slowed down if we delay the emptying of the stomach.  Explain why eating food with the alcohol will slow down the emptying of the stomach.  Your answer should include the hormones that are involved, and the stimulus for their release.   (8 points total)

5.  Scientists have tried to develop a male contraceptive, by injecting males with a drug that mimics the effect of progesterone.  Explain how such a drug would inhibit spermatogenesis in males.   (6 points total, for any 6 out of these 7 points)

6  During exercise, body temperature increases, and we respond by taking off clothes.  When infected with the influenza virus and developing a fever, body temperature increases, and we respond by putting on more clothes or cuddling under the blankets.  If body temperature rises in both situations, why is our response different?  To answer this, draw two flowcharts.  List the steps that occur.  Your answer should include the cells, anatomical structures, signaling molecules that are involved.  (12 points total)

7.  One person is given glucose by mouth, another is injected with the same amount of glucose into the blood.  Which person will have a higher peak in blood glucose.  Why?