Relies on release of chemicals that bind to specific receptors

1. Which of these characteristics is exclusive to the endocrine system, when compared with the nervous system? Relies on release of chemicals that bind to specific receptors Relies primarily on negative feedback mechanisms Uses epinephrine and norepinephrine as chemical messengers Effective in coordinating cell, tissue, and organ activities on a sustained, long-term basis

2. Which of the following statements is true of peptide hormones? They are derived from cholesterol. They are synthesized as prohormones and convert to active hormones before or after secretion. They are also called biogenic amines and are synthesized from tyrosine. They are important paracrine factors that coordinate cellular activities.

3. If levels of a certain hormone are high, which of the following will happen? A second messenger brings more of that hormone into the cell. There will be a decrease in the number of cell receptors for that hormone and cells become less sensitive to it. A G protein will bind to that hormone. There will be an increase in the number of cell receptors for that hormone and cells become more sensitive to it.

4. How does the presence of a molecule that blocks adenylate cyclase affect the activity of a hormone that produces its cellular effects by way of the second messenger cAMP? It prevents synthesis of the hormone. It enhances the action of the hormone. It increases sensitivity to the hormone. It decreases speed of hormonal changes.

5. How does the hypothalamus regulate nervous and endocrine activities? It secretes regulatory hormones that influence endocrine cells in the pituitary. It has autonomic centers that exert direct neural control over endocrine cells of the adrenal medullae. Hypothalamic neurons synthesize hormones and transport them along axons within the infundibulum. All of these are correct.

6. What is critically important about the vascular arrangement of the hypophyseal portal system? It provides efficient means of ensuring that all hypothalamic hormones will reach target cells in the adenohypophysis before being diluted in general circulation. It ensures that all hormones destined for the pituitary are diluted in general circulation before entering the adenohypophysis. It ensures that RH from the hypothalamus synthesizes the correct amount of a specific hormone. None of these is correct.

7. Why do high levels of cortisol, a steroid hormone from the suprarenal cortex, cause a decrease in the pituitary secretion of ACTH? Because high levels of cortisol stimulates other steroid hormones. The hormones act in a synergistic manner. Because ACTH participates in a negative feedback loop with cortisol. CRH from the hypothalamus inhibits ACTH release.

8. A blood sample shows elevated levels of somatomedins. Which pituitary hormone will be elevated as well? Thyroid stimulating hormone Growth hormone Oxytocin Adrenocorticotropic hormone

9. What is the role of FSH in males? It stimulates production of sex hormones. It stimulates the breakdown of stored triglycerides by adipocytes. It stimulates sustenacular cells, which then promotes maturation of sperm. It stimulates smooth muscle contraction in the ductus deferens and prostate gland.

10. If a person has been drinking alcohol, how is ADH released by the neurohypophysis affected? More ADH is released to increase the solute concentration of blood and urine. ADH secretion is inhibited by drinking alcohol. It does not change at all. ADH secretion increases causes vasoconstriction and increased blood pressure.

11. Iodine deficiency in the diet produces what symptom? Increased rate of metabolism Increased body temperature Exaggerated response to physiological stress Goiter

12. Which of the following is not an effect of thyroid hormones on major organ systems? Increased heart rate and force of contraction Increased sensitivity to sympathetic stimulation Decreased turnover of minerals in bone Stimulation of red blood cell formation

13. The removal of the parathyroid glands result in a decrease in the blood concentration of which important mineral? Calcium ions Phosphate ions Sodium ions Potassium ions

14. Failure of the zona glomerulosa to secrete aldosterone would result in _____. Decreased formation and secretion of calcitrol Enhanced reabsorption of Ca2+ at the kidneys Loss of Na+, K+ retention, and decreased reabsorption of water at the kidneys None of these is correct

15. Secretion of cortisol by the zona fasciculata _____ in the liver and has a(n) _______ effect on CRH in the hypothalamus? Decreases glucose synthesis/stimulatory Increases glucose synthesis/inhibitory Increases androgen production/antagonistic Decreases glycogen synthesis/synergistic

16. In what ways are hormonal effects of E and NE from the suprarenal medulla similar to the effects of glucocorticoids from the zona fasciculata? Hormones from both are under the ultimate control of the sympathetic nervous system. Both increase cardiac activity and blood pressure. Both are stimulated by angiotensin II. Both increase blood glucose levels and promote the breakdown of stored fats into fatty acids.

17. Increased amounts of sunlight inhibit the production of which hormone? Prolactin Melanocyte stimulating hormone Aldosterone Melatonin

18. Melatonin is well known for its role in regulating circadian rhythm. What are two other functions of melatonin? Promotes muscle mass and supports libido in females Testicular feminization and gynecomastia in males Inhibits reproductive functions and protects CNS neurons from free radicals Promotes early puberty and increased rates of oxygen consumption

19. Which pancreatic cell type is paired with the hormone it produces? Alpha cells/pancreatic polypeptide F cells/a hormone identical to growth hormone-inhibiting hormone Beta cells/insulin Delta cells/glucagon

20. Cells in the ___are insulin independent, which means that they can _____. Brain, kidneys, and digestive tract/absorb glucose without insulin stimulation Liver/produce glucose Pancreas and suprarenal cortex/produce insulin Suprarenal cortex and suprarenal medulla/function without insulin

21. Why are diabetics continuously thirsty and why do they frequently urinate? Less water is reclaimed by osmosis in the kidneys. Water loss reduces blood volume, promoting secretion of ADH. Glucose is lost in the urine, which increases blood volume. 1 and 2 are correct.

22. Which of the following is an effect of glucagon? Accelerated glucose uptake and utilization Breakdown of triglycerides in adipose tissue Stimulation of amino acid absorption and protein synthesis Stimulation of glycogen formation

23. What is the effect of renin secretion by the kidneys? Stimulation of Ca2+ and PO4 absorption along the digestive tract Stimulates the production of red blood cells by bone marrow Converts angiotensinogen to angiotensin I Inhibits secretion of ADH and aldosterone

24. Insulin lowers the level of glucose in the blood, and then glucagon causes glucose levels to rise. What is this type of hormonal interaction called? Synergistic Permissive Antagonistic Integrative

25. Deficiencies of which hormones impede normal skeletal development? GH, thyroid hormone, PTH, and reproductive hormones Prolactin, FSH, LH, GH Thyroid hormone, melatonin, PTH, calcitonin GH, TSH, ACTH, FSH

26. All of the following except ___ occur during the resistance phase of the general adaptation syndrome. Conservation of glucose for neural tissues Mobilization of remaining lipid and protein reserves Conservation of Na+ and loss of K+ and H+ Increased mental alertness and increased blood pressure