Midterm 3 Key

Multiple choice:   As always, choose the best answer for each question.  Answer on your scantron form.  Each question (except #1) is worth 3 points.

1.      Fill in your scantron form as follows:  (1 point)

·        Write in your name in the upper left (last name first) and bubble it in.

·        If you wish to retrieve your exam score through the web and did not give me a PIN previously (or want to change it), write and bubble in a number in the “Social Security Number” section.  Be sure you remember it!

·        Sign your form in the upper right.

a.      Mmm…free point.

b. – e.  D’oh!

2.      The tough outer layer of the main gastrointestinal tract is known as the

a.       mucosa.

b.      lumen.

c.       muscularis externa.

d.      serosa.

e.       submucosa.

3.      By definition, “digestion” would include which of the following?

a.       The mechanical or physical breakdown of food.

b.      The chemical breakdown of food.

c.       The transport of nutrients across the gut epithelium.

d.      Two of the above.

e.       All of the above.

4.      The activity of the stomach is increased by

a.       increased release of the hormone gastrin.

b.      increased activity of the parasympathetic nervous system.

c.       increased activity of the sympathetic nervous system.

d.      a and b.

e.       a and c.

5.      In the stomach, mucus is secreted by the

a.       chief cells.

b.      gastric cells.

c.       goblet cells.

d.      mucosal cells.

e.       parietal cells.

6.      The injection of a quantity of acid directly into the upper end of the small intestine would most strongly effect the secretion of which of the following hormones?

a.       Cholecystokinin

b.      Gastrin

c.       Glucose-dependent insulinotropic peptide

d.      Norepinephrine

e.       Secretin

7.      The liver is responsible for release of which of the following into the small intestine?

a.      Sodium bicarbonate

b.      Lipases

c.       Amylase

d.      All of the above.

e.       None of the above.

8.      Bile salts are important in the digestion of fats because

a.      they help break fat droplets up into much smaller volumes.

b.      they digest fats into fatty acids and glycerol.

c.       they help package fats up into chylomicrons.

d.      Two of the above.

e.       All of the above.

9.      The level of leptin in the blood is determined primarily by

a.       the level of glucose in the blood.

b.      the amount of glycogen in the liver.

c.       the level of fatty acids in the blood.

d.      the amount of fat stored in the body.

e.       metabolic rate.

10.  If a substance filtered into the kidneys is neither secreted nor reabsorbed, its concentration in the final urine compared to its concentration in the initial glomerular filtrate would be

a.      much higher.

b.      slightly higher.

c.       about the same.

d.      slightly lower.

e.       much lower.

11.  The blood vessel most closely associated with the loop of Henle is the

a.       afferent arteriole.

b.      efferent arteriole.

c.       glomerulus.

d.      peritubular capillary.

e.       vasa recta.

12.  Which of the following is not reabsorbed in the proximal tubule?

a.       Glucose

b.      Sodium

c.       Urea

d.      Water

e.       All of the above are reabsorbed in the proximal tubule.

13.  The loop of Henle is an example of

a.       a counter-current exchanger.

b.      a counter-current multiplier.

c.       a portal exchange system.

d.      tubuloglomeric feedback.

e.       Jacob Henle’s ability to get something named after himself.

14.  In the collecting duct, final urine concentration is controlled mainly by

a.       the diffusion of solutes into the urine.

b.      the active transport of solutes into of the urine.

c.       the osmotic movement of water out of the urine.

d.      the active transport of water out of the urine.

e.       Two of the above.

15.  Increased levels of anti-diuretic hormone are released in response to

a.       decreased blood pressure.

b.      increased plasma osmolarity.

c.       decreased urine flow in the distal tubule.

d.      Two of the above.

e.       None of the above.

16.  Increased levels of angiotensinogen are released in response to

a.       decreased blood pressure.

b.      increased plasma osmolarity.

c.       decreased urine flow in the distal tubule.

d.      Two of the above.

e.       None of the above.

17.  Low venous blood pressure ultimately results in low arterial blood pressure because

a.       low venous BP reduces heart rate.

b.      low venous BP reduces stroke volume.

c.       low venous BP reduces blood flow to the coronary arteries.

d.      low venous BP reduces capillary resistance.

e.       low venous BP creates a stronger arterial-venous pressure gradient.

18.  The only way to actually increase the volume of your extra-cellular fluid is to

a.       increase urine concentration.

b.      decrease urine volume.

c.       decrease urine concentration.

d.      increase urine volume.

e.       take in water.

19.  In human females, meiosis I of the oocyte is completed

a.       when the woman is still a fetus.

b.      at puberty.

c.       at the beginning of follicular development.

d.      at ovulation.

e.       at fertilization.

20.  The corpus luteum, when fully developed, produces physiologically important amounts of

a.       estrogen.

b.      progesterone.

c.       inhibin.

d.      Two of the above.

e.       All of the above.

21.  The uterine endometrium is ready for implantation during the.

a.       chorionic phase.

b.      follicular phase.

c.       menstrual phase.

d.      proliferative phase.

e.       secretory phase.

22.  Except during the emission-ejaculation sequence, mature sperm are found mainly in the

a.       testes.

b.      epididymus.

c.       vas deferens.

d.      ejaculatory duct.

e.       urethra.

23.  The erection of the penis in human males is relies mainly on

a.      blood pressure.

b.      the penile muscle.

c.       the pubic bone.

d.      the prostate gland.

e.       the bulbourethral gland.

24.  The “window of opportunity” each month for fertilization in humans is about

a.       twelve hours.

b.      one day.

c.       three days.

d.      one week.

e.       three weeks.

25.  During month seven of pregnancy, the progesterone levels in the mother’s blood are due mainly to release of the hormone from the

a.       anterior pituitary.

b.      corpus luteum.

c.       placenta.

d.      Two of the above.

e.       All of the above.

26.  Milk secretion in females is promoted by

a.       estrogen.

b.      luteinizing hormone.

c.       oxytocin.

d.      progesterone.

e.       prolactin.

Short answer:   Write a concise answer to each of the following questions.  Your answers should fit in the spaces provided.  Each question is worth 4 points.

27.  Discuss the enzymatic breakdown of proteins in the digestive system.  Specifically, indicate the enzymes involved and for each where it comes from, how it is activated, and where in the GI tract its activity occurs.

28.  Consider a person who hyposecretes glucagon.  How do you think her blood glucose levels would compare to a normal person’s during both the absorptive state and the post-absorptive state?  Explain your answer.

29.  If someone were injected with a drug that poisoned the sodium transporters in the ascending loop of Henle and initial distal tubule so that they ceased functioning, how might this affect the person’s ability to make a hyperosmotic urine?  How about a hyposmotic urine?  Explain your answer.

30.  Using a flow chart or a list of events, describe the hormonal pathway involving atrial natriuretic factor.  Be sure to indicate the source of the hormone, what controls its release, and what the effects are.

31.  What should be the respiratory response to a metabolic alkalosis, and how will this response affect blood pH?

32.  Diagram or describe the hormonal pathways involved in promoting spermatogenesis in males.  Be sure to include the tissues affected by each hormone.