CHAPTER 18 Endocrine Glands

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27. Which of the following is not a hormone produced by the ovaries?a. estrogen c. prolactin e. relaxinb. progesterone d. inhibin

28. Melatonina. is produced by the posterior pituitary.b. production increases as day length increases.c. inhibits the development of the reproductive system.d. increases GnRH secretion from the hypothalamus.e. decreases the tendency to sleep.

29. Which of these substances, produced by many body tissues, can promoteinflammation, pain, and vasodilation of blood vessels?a. endorphins c. thymosin e. prostaglandinsb. enkephalins d. epidermal growth factor

30. Which of these secretions does not decrease with aging of the endo-crine system?a. GH secretion c. thyroid hormone secretionb. melatonin secretion d. parathyroid hormone secretion

Answers in appendix E

1. The hypothalamohypophysial portal system connects the hypothala-mus with the anterior pituitary. Why is such a special circulatory sys-tem advantageous?

2. A patient exhibits polydipsia (thirst), polyuria (excess urine production),and urine with a low specific gravity (contains few ions and no glucose).If you wanted to reverse the symptoms, would you administer insulin,glucagon, ADH, or aldosterone? Explain.

3. A patient complains of headaches and visual disturbances. A casualglance reveals enlarged finger bones, a heavy deposition of boneover the eyes, and a prominent jaw. The doctor determines that theheadaches and visual disturbances result from increased pressurewithin the skull and that the presence of a pituitary tumor is affect-ing hormone secretion. Name the hormone causing the problem, andexplain why increased pressure exists within the skull.

4. Most laboratories are able to determine blood levels of TSH, T 3 , andT 4 . Given that ability, design a method of determining whether hyper-thyroidism in a patient results from a pituitary abnormality or fromthe production of a nonpituitary thyroid stimulatory substance.

5. Over the past year, Julie has gradually gained weight. The increasein adipose tissue is distributed over her trunk, face, and neck, and hermuscle mass appears to be decreased. Julie also feels weak and bruiseseasily. Her physician suspects Cushing syndrome and orders a seriesof blood tests. The results reveal elevated blood levels of cortisol andACTH. There is no evidence of an extrapituitary source of ACTH.Predict the cause of Julie’s condition and the treatments that are likelyto be recommended.

6. An anatomy and physiology instructor asks two students to predicta patient’s response to chronic vitamin D deficiency. One studentclaims the person would suffer from hypocalcemia. The other studentclaims the calcium levels would remain within their normal range,although at the low end, and that bone reabsorption would occur tothe point that advanced osteomalacia might occur. With whom do youagree, and why?

7. A patient arrives at the emergency room in an unconscious condi-tion. A medical emergency bracelet reveals that he has diabetes. Thepatient is in either diabetic coma or insulin shock. How can you tellwhich, and what treatment do you recommend for each condition?

8. Predict some of the consequences of exposure to intense and pro-longed stress.

9. Katie was getting nervous. At 16, she was the only one in her group offriends who had not started menstruating. Katie had always dreamedof having three beautiful children someday and she was worried. Hermother took her to see Dr. Josephine, who ordered several blood tests.When the results came back, Dr. Josephine gently explained to Katieand her mother that Katie would never be able to have children andwould never menstruate. Dr. Josephine then asked Katie to wait in theouter room while she spoke privately to her mother. She explained toKatie’s mom that Katie has androgen insensitivity syndrome. ThoughKatie is genetically male and her gonads produce more of the malereproductive hormone, testosterone, than the female reproductivehormone, estrogen, Katie did not reflect the tissue changes expected.What malfunction in Katie’s body would cause this? Why does Katie’sbody look feminine if she is genetically male?

Answers in appendix F