Block 5 Endocrine Physiology BRS

30 Questions | Total Attempts: 966

SettingsSettingsSettings
Please wait...
Block 5 Endocrine Physiology BRS

The endocrine system is a control system of ductless glands that secrete hormones within specific organs. The parts of the endocrine system transfer information from one set of cells to another to coordinate the functions of different parts of the body. Take up this review quiz on block 5 on the endocrine physiology and refresh your memory.


Questions and Answers
  • 1. 
    The increase shown at point A is caused by the effect of
    • A. 

      Estrogen on the anterior pituitary

    • B. 

      Progesterone on the hypothalamus

    • C. 

      Follicle-stimulating hormone (FSH) on the ovary

    • D. 

      Luteinizing hormone (LH) on the anterior pituitary

    • E. 

      Prolactin on the ovary

  • 2. 
    Blood levels of which substance are described by curve B?
    • A. 

      Estradiol

    • B. 

      Estriol

    • C. 

      Progesterone

    • D. 

      FSH

    • E. 

      LH

  • 3. 
    The source of the increase in concentration indicated at point C is the
    • A. 

      Hypothalamus

    • B. 

      Anterior pituitary

    • C. 

      Corpus luteum

    • D. 

      Ovary

    • E. 

      Adrenal cortex

  • 4. 
    The source of the increase in concentrationat point D is the
    • A. 

      Ovary

    • B. 

      Adrenal cortex

    • C. 

      Corpus luteum

    • D. 

      Hypothalamus

    • E. 

      Anterior pituitary

  • 5. 
    The cause of the sudden increase shown at point E is
    • A. 

      Negative feedback of progesterone on the hypothalamus

    • B. 

      Negative feedback of estrogen on the anterior pituitary

    • C. 

      Negative feedback of follicle-stimulating hormone (FSH) on the ovary

    • D. 

      Positive feedback of FSH on the ovary

    • E. 

      Positive feedback of estrogen on the anterior pituitary

  • 6. 
    A woman has hypocalcemia, hyperphosphatemia, and decreased urinary phosphate excretion. Injection of parathyroid hormone (PTH) causes an increase in urinary cyclic adenosine monophosphate (cAMP). The most likely diagnosis is
    • A. 

      Primary hyperparathyroidism

    • B. 

      Vitamin D intoxication

    • C. 

      Vitamin D deficiency

    • D. 

      Hypoparathyroidism after thyroid surgery

    • E. 

      Pseudohypoparathyroidism

  • 7. 
    Which of the following hormones acts on its target tissues by a steroid hormone mechanism of action?
    • A. 

      Thyroid hormone

    • B. 

      Parathyroid hormone (PTH)

    • C. 

      Antidiuretic hormone (ADH) on the collecting duct

    • D. 

      Rl adrenergic agonists

    • E. 

      Glucagon

  • 8. 
    A man who has galactorrhea is found to have a prolactinoma. His physician treats him with bromocriptine, which eliminates the galactorrhea. The basis for the therapeutic action of bromocriptine is that it
    • A. 

      Antagonizes the action of prolactin on the breast

    • B. 

      Enhances the action of prolactin on the breast

    • C. 

      Inhibits prolactin release from the anterior pituitary

    • D. 

      Inhibits prolactin release from the hypothalamus

    • E. 

      Enhances the action of dopamine on the anterior pituitary

  • 9. 
    Which of the following hormones originates in the anterior pituitary?
    • A. 

      Dopamine

    • B. 

      Growth hormone releasing hormone (GHRH)

    • C. 

      Somatostatin

    • D. 

      Gonadotropin-releasing hormone (GnRH)

    • E. 

      Thyroid-stimulating hormone (TSH)

    • F. 

      Oxytocin

    • G. 

      Testosterone

  • 10. 
    Which of the following functions of the Sertoli cells mediates negative feedback control of follicle-stimulating hormone (FSH) secretion?
    • A. 

      Synthesis of inhibin

    • B. 

      Synthesis of testosterone

    • C. 

      Aromatization of testosterone

    • D. 

      Maintenance of the blood—testes barrier

  • 11. 
    Which of the following substances is derived from proopiomelanocortin (POMC)?
    • A. 

      Adrenocorticotropic hormone (ACTH)

    • B. 

      Follicle-stimulating hormone (FSH)

    • C. 

      Melatonin

    • D. 

      Cortisol

    • E. 

      Dehydroepiandrosterone

  • 12. 
    Which of the following inhibits the secretion of growth hormone by the anterior pituitary?
    • A. 

      Sleep

    • B. 

      Stress

    • C. 

      Puberty

    • D. 

      Somatomedins

    • E. 

      Starvation

    • F. 

      Hypoglycemia

  • 13. 
    Selective destruction of the zona glomerulosa of the adrenal cortex would produce a deficiency of which hormone?
    • A. 

      Aldosterone

    • B. 

      Androstenedione

    • C. 

      Cortisol

    • D. 

      Dehydroepiandrosterone

    • E. 

      Testosterone

  • 14. 
    Which of the following explains the suppression of lactation during pregnancy?
    • A. 

      Blood prolactin levels are too low for milk production to occur

    • B. 

      Human placental lactogen levels are too low for milk production to occur

    • C. 

      The fetal adrenal gland does not produce sufficient estriol

    • D. 

      Blood levels of estrogen and progesterone are high

    • E. 

      The maternal anterior pituitary is suppressed

  • 15. 
    Which step in steroid hormone biosynthesis, if inhibited, blocks the production of all androgenic compounds but does not block the production of glucocorticoids?
    • A. 

      Cholesterol —> pregnenolone

    • B. 

      Progesterone —> 11-deoxycorticosterone

    • C. 

      17-Hydroxypregnenolone —> dehydroepiandrosterone

    • D. 

      Testosterone -, estradiol

    • E. 

      Testosterone —> dihydrotestosterone

  • 16. 
    A woman has hirsutism, hyperglycemia, obesity, muscle wasting, and increased circulating levels of adrenocorticotropic hormone (ACTH). The most likely cause of her symptoms is
    • A. 

      Primary adrenocortical insufficiency (Addison's disease)

    • B. 

      Pheochromocytoma

    • C. 

      Primary overproduction of ACTH (Cushing's disease)

    • D. 

      Treatment with exogenous glucocorticoids

    • E. 

      Hypophysectomy

  • 17. 
    Which of the following decreases the conversion of 25-hydroxycholecalciferol to 1,25- dihydroxycholecalciferol?
    • A. 

      A diet low in Ca2+

    • B. 

      Hypocalcemia

    • C. 

      Hyperparathyroidism

    • D. 

      Hypophosphatemia

    • E. 

      Chronic renal failure

  • 18. 
    Increased adrenocorticotropic hormone (ACTH) secretion would be expected in patients
    • A. 

      With chronic adrenocortical insufficiency (Addison's disease)

    • B. 

      With primary adrenocortical hyperplasia

    • C. 

      Who are receiving glucocorticoid for immunosuppression after a renal transplant

    • D. 

      With elevated levels of angiotensin II

  • 19. 
    Which of the following would be expected in a patient with Graves' disease?
    • A. 

      Cold sensitivity

    • B. 

      Weight gain

    • C. 

      Decreased 02 consumption

    • D. 

      Decreased cardiac output

    • E. 

      Drooping eyelids

    • F. 

      Atrophy of the thyroid gland

    • G. 

      Increased thyroid-stimulating hormone (TSH) levels

    • H. 

      Increased triiodothyronine (r3) levels

  • 20. 
    Blood levels of which of the following substances is decreased in Graves' disease?
    • A. 

      Triiodothyronine (T3)

    • B. 

      Thyroxine (r,)

    • C. 

      Diiodotyrosine (DIT)

    • D. 

      Thyroid-stimulating hormone (TSH)

    • E. 

      Iodide (I-)

  • 21. 
    Which of the following hormones acts by an inositol 1,4,5-triphosphate (IP 3)-Ca2+ mechanism of action?
    • A. 

      1,25-Dihydroxycholecalciferol

    • B. 

      Progesterone

    • C. 

      Insulin

    • D. 

      Parathyroid hormone (PTH)

    • E. 

      Gonadotropin-releasing hormone (GnRH)

  • 22. 
    Which step in steroid hormone biosynthesis is stimulated by adrenocorticotropic hormone (ACTH)?
    • A. 

      Cholesterol-* pregnenolone

    • B. 

      Progesterone —> 11-deoxycorticosterone

    • C. 

      17-Hydroxypregnenolone dehydroepiandrosterone

    • D. 

      Testosterone —> estradiol

    • E. 

      Testosterone -+ dihydrotestosterone

  • 23. 
    The source of estrogen during the second and third trimesters of pregnancy is the
    • A. 

      Corpus luteum

    • B. 

      Maternal ovaries

    • C. 

      Fetal ovaries

    • D. 

      Placenta

    • E. 

      Maternal ovaries and fetal adrenal gland

    • F. 

      Maternal adrenal gland and fetal liver

    • G. 

      Fetal adrenal gland, fetal liver, and placenta

  • 24. 
    Which of the following causes increased aldosterone secretion?
    • A. 

      Decreased blood volume

    • B. 

      Administration of an inhibitor of angiotensin-converting enzyme (ACE)

    • C. 

      Hyperosmolarity

    • D. 

      Hypokalemia

  • 25. 
    Secretion of oxytocin is increased by
    • A. 

      Milk ejection

    • B. 

      Dilation of the cervix

    • C. 

      Increased prolactin levels

    • D. 

      Increased extracellular fluid (ECF) volume

    • E. 

      Increased serum osmolarity

Back to Top Back to top