Ch5 Cell Signaling And The Hormonal Test Bank + Answers

Chapter 05

Cell Signaling and the Hormonal Responses to Exercise

Multiple Choice Questions
 

1. While hormones circulate to all tissues, some affect only a few tissues. This is due to the 
A. plasma concentration of the hormone.
B. training state of the subject.
C. type of receptor at the tissue.
D. concentration of the hormone.

2. The concentration of a hormone can be increased by 
A. decreasing the rate at which it is metabolized.
B. increasing the number of receptors.
C. increasing the rate at which it is excreted.
D. increasing the plasma volume.

3. When adenylate cyclase is activated by a hormone, the concentration of cyclic AMP increases in the cell even though the hormone does not enter the cell. This is an example of the __________________ mechanism of hormone action. 
A. altering membrane transport
B. altering activity of DNA
C. second messenger
D. all of above

4. Steroid hormones exert their effect by 
A. activating adenylate cyclase.
B. altering the activity of DNA.
C. blocking the effect of cyclic AMP.
D. causing an inflammation response.

5. Growth hormone 
A. is released from the posterior pituitary.
B. spares plasma glucose during exercise.
C. is only elevated in children and adolescents.
D. All of the above are

6. If the thyroid gland does not produce a sufficient amount of T₃ or T₄, the resting metabolic rate will 
A. increase.
B. decrease.
C. remain the same.

7. Which of the following hormones is secreted by the thyroid gland and plays a role in the regulation of plasma calcium levels? 
A. thyroxine
B. triiodothyronine
C. calcitonin
D. parathyroid hormone

8. Which of the following is a hormone that is secreted by the adrenal medulla? 
A. epinephrine
B. aldosterone
C. cortisol
D. angiotensin II

9. Which of the following may be related to changes in mood and pain perception during endurance exercise? 
A. catecholamines
B. glucocorticoids
C. somatomedins
D. endorphins

10. The decrease in plasma volume and the increase in the osmolality of the plasma during exercise results in _________________ in antidiuretic hormone. 
A. an increase
B. a decrease
C. no change

11. Given the importance of maintaining the plasma glucose concentration during exercise, insulin secretion would be expected to ______________ during exercise. 
A. increase
B. decrease
C. remain the same

12. A hormone that is released from the pancreas at a higher rate during exercise to mobilize liver glucose and adipose tissue fatty acids is 
A. glucagon.
B. somatostatin.
C. insulin.
D. none of the above.

13. The term describing the cessation of the menstrual cycle resulting from lower estrogen levels in some female athletes is 
A. dysmenorrhea.
B. eumenorrhea.
C. amenorrhea.
D. menarche.

14. Muscle glycogen breakdown is stimulated by the catecholamines. It is also stimulated by 
A. elevated H⁺ concentration.
B. increased intracellular Ca⁺⁺.
C. both a and b.
D. neither a nor b—it is stimulated only by the catecholamines.

15. Which of the following hormones is believed to exert a "permissive" effect on the mobilization of glucose from liver and FFA from adipose tissue? 
A. epinephrine
B. T₃ and T₄
C. insulin
D. glucagon

16. During exercise of about 40% VO₂ max, the concentration of plasma cortisol 
A. is lower than at rest.
B. is higher than at rest.
C. remains the same as at rest.

17. The primary effect of the elevated plasma concentration of growth hormone during intense exercise is to 
A. increase the synthesis of contractile protein in muscle.
B. promote long bone growth.
C. favor the mobilization of FFA and reduces tissue use of blood glucose.
D. none of the above.

18. As a result of training, the sympathetic nervous system's response to a fixed submaximal work rate 
A. is increased.
B. is decreased.
C. remains the same.

19. The changes in the plasma concentration of most of the hormones during maximal exercise would stimulate fatty acid mobilization from adipose tissue. The plasma-free fatty acid concentration, however, actually decreases. Why does this occur? 
A. Fatty acid supply is depleted.
B. Hormones are ineffective in maximal work.
C. Lactic acid interferes with fatty acid mobilization.
D. High insulin levels secreted during maximal exercise interfere with fatty acid mobilization.

20. During exercise, blood glucose concentration is maintained by all of the following except 
A. elevated mobilization of FFA from adipose tissue.
B. increased rate of gluconeogenesis.
C. blocking entry of glucose into cells.
D. elevated concentration of insulin.

21. Insulin secretion would be highest 
A. during prolonged exercise.
B. as exercise intensity increases.
C. after a meal.
D. It would be equally high after all of the above.

22. The mobilization of free fatty acids from adipose tissue and glucose from liver glycogen would be stimulated by 
A. an increase in insulin and an increase in glucagon.
B. a decrease in insulin and an increase in glucagon.
C. an increase in insulin and a decrease in glucagon.
D. a decrease in insulin and a decrease in glucagon.

23. During exercise, epinephrine and norepinephrine stimulate liver glycogenolysis indirectly by 
A. increasing glucagon secretion from the pancreas.
B. increasing insulin secretion from the pancreas.
C. increasing the uptake of FFA by muscle.
D. lowering plasma cortisol concentration.

24. Which of the following hormones is part of the General Adaptive Syndrome and is called the "stress" hormone? 
A. epinephrine
B. renin
C. cortisol
D. insulin

25. Which of the following hormones is secreted from adipose tissue? 
A. leptin
B. adiponectin
C. both a and b
D. neither a nor b

/ Questions

26. When a drug is given to block the adrenergic receptors during exercise, muscle glycogen utilization is reduced.

27. Chronic exposure to high levels of a hormone results in "up regulation" of receptors.

28. Blood epinephrine levels increase as exercise intensity increases, but decrease as exercise duration increases.

29. Glucagon secretion increases during exercise, which decreases liver glycogen stores in order to maintain blood glucose concentration.

30. Growth hormone secretion increases during exercise and decreases during sleep.

31. Even though the concentration of insulin decreases during exercise, the muscle can still take up large quantities of plasma glucose. This is due, in part, to the recruitment of more glucose transporters.