Ch 16: Endocrine System Flashcards

1) The pineal gland is used as a brain orientation landmark for brain X rays.

2) Calcitonin is the main regulator of blood calcium levels.

3) The hormone that raises blood sugar levels is insulin.

4) Addison's disease is usually due to an insufficient output of glucocorticoids only.

5) Both "turn on" factors (hormonal, humoral, and neural stimuli) and "turn off" factors (feedback inhibition and others) may be modulated by the activity of the nervous system.

6) ACTH stimulates the adrenal cortex to release corticosteroid hormones.

7) LH is also referred to as a gonadotropin.

8) Examples of adrenal gland short-term stress responses include immune system suppression and retention of salt and water by the kidneys.

9) Oxytocin is a strong stimulant of uterine contractions.

10) Enteroendocrine cells of the GI tract produce some hormones that are chemically identical to neurotransmitters.

11) Type 2 diabetes mellitus may reflect declining receptor sensitivity to insulin rather than decreased insulin production.

12) The prime metabolic effect of cortisol is gluconeogenesis.

13) The beta cells in the pancreatic islets produce insulin.

14) Most type 2 diabetics do NOT produce insulin.

15) Aldosterone is the most potent mineralocorticoid produced by the adrenal glands but the least abundant.

16) Atrial natriuretic peptide is a hormone that controls blood pressure in part by increasing the urinary excretion of sodium.

17) Hypersecretion of catecholamines (epinephrine and norepinephrine) can result in hypertension.

18) Thyroid hormone production requires the presence of both iodine and calcium.

19) Many hormones synthesized in the gastrointestinal tract are chemically identical to brain neurotransmitters.

20) Oxytocin and ADH are produced in the posterior pituitary.

21) Iodine is an essential element required for the synthesis of thyroxine.

22) The endocrine gland that is probably malfunctioning if a person has a high metabolic rate is the parathyroid.

23) Growth hormone solely exerts its influence by targeting other endocrine glands to produce hormones.

24) Glucocorticoids are steroid hormones that usually enhance the immune responses when an individual is suffering from severe stress.

25) Direct gene activation involves a second-messenger system.

26) All amino acid based hormones are lipid soluble and can cross the plasma membrane.

27) All anterior pituitary hormones EXCEPT growth hormone affect their target cells via a cyclic AMP second-messenger system.

1) Gluconeogenesis, the formation of glucose from fats and proteins, is due to the action of ________. A) insulin B) secretin C) cortisol D) aldosterone

2) Normal development of the immune response is due in part to hormones produced by the ________. A) thyroid gland B) thymus gland C) adrenal medulla D) pancreas

3) Virtually all amino acid-based hormones exert their signaling effects through intracellular ________. A) nucleotides B) calcium C) deactivating ions D) second messengers

4) Which of the following is NOT a category of endocrine gland stimulus? A) neural B) humoral C) enzymatic D) hormonal

5) Chemical substances secreted by cells into the extracellular fluids that travel through the blood and regulate the metabolic function of other cells in the body are called ________. A) enzymes B) antibodies C) hormones D) proteins

6) The hypothalamic-hypophyseal tract ________. A) runs through the infundibulum B) conducts aldosterone to the hypophysis C) connects the hypophysis to the pituitary gland D) is the site of prolactin synthesis

7) Which of the following is NOT a cardinal sign of diabetes mellitus? A) polycythemia B) polyuria C) polydipsia D) polyphagia

8) Which of the following can act on receptors inside the target cell that directly activate specific genes? A) growth hormone B) melatonin C) testosterone D) calcitonin

9) Oxytocin ________. A) exerts its most important effects during menstruation B) release is an example of a positive feedback control mechanism C) is an anterior pituitary secretion D) controls milk production

10) Antidiuretic hormone (ADH) ________. A) promotes dehydration B) increases urine production C) secretion is inhibited by alcohol D) is produced by the anterior pituitary

11) Which of the following is NOT a type of hormone interaction? A) feedback B) permissiveness C) antagonism D) synergism

12) Which of the following is NOT a change typically produced by a hormonal stimulus? A) induces secretory activity B) alters plasma membrane permeability C) stimulates production of an action potential D) activates or deactivates enzymes

13) Which of the following is NOT a change that may be caused by hormonal stimulus? A) an increase in enzyme synthesis B) stimulation of mitosis C) a change in membrane potential D) direct control of the nervous system

14) The ability of a specific tissue or organ to respond to the presence of a hormone is dependent on ________. A) nothingall hormones of the human body are able to stimulate any and all cell types because hormones are powerful and nonspecific B) the location of the tissue or organ with respect to the circulatory path C) the membrane potential of the cells of the target organ D) the presence of the appropriate receptors on the cells of the target tissue or organ

15) The posterior lobe of the pituitary gland is NOT a true endocrine gland because ________. A) embryonically it was an endocrine tissue, but in the adult human it is no longer functional B) it is only a hormone storage area that receives hormones from the hypothalamus for release C) it is unable to function as an endocrine tissue because it is actually part of the neural system due to its location D) it is strictly a part of the neural system and has little or nothing to do with hormonal release

16) Steroid hormones exert their action by ________. A) binding cell receptors and initiating cAMP activity B) entering the cell and activating mitochondrial DNA C) entering the nucleus of a cell and initiating or altering the expression of a gene D) activating the hypothalamic release of regulating hormones

17) The second-messenger mechanism of hormone action operates by ________. A) synthesizing more than one hormone at a time B) binding to specific receptors and employing the services of G proteins and cAMP C) increasing the basal metabolic rate in the target organ D) altering gene expression in the nuclear DNA

18) Hormones often cause a cell to elicit multiple responses. This is because ________. A) during protein kinase activation, enzymes phosphorylate many other enzymes B) there are thousands of receptors on the cell membrane C) the receptors bind to several hormones at the same time D) the protein kinases are rapidly metabolized into functional amino acids

19) Cells that respond to peptide hormones usually do so through a sequence of biochemical reactions involving receptor and kinase activation. In order for cells to respond, it is necessary for first and second messengers to communicate. This is possible because ________. A) peptide hormones are converted by cell membranes enzymes into second messengers B) G protein acts as the link between first and second messengers C) the hormone receptor complex moves into the cytoplasm as a unit D) hormones alter cellular operations through direct stimulation of a gene

20) Thyroid hormone (a small iodinated amine) enters target cells in a manner similar to ________. A) steroid hormones, because both diffuse easily into target cells B) glucagon, because the structure of glucagon is similar to that of thyroid hormone C) insulin, because insulin is a small peptide D) growth hormone, because the thyroid works synergistically with thyroid hormone

21) Which anterior pituitary hormone does NOT target another endocrine gland? A) adrenocorticotropic hormone (ACTH) B) growth hormone C) luteinizing hormone D) follicle-stimulating hormone

22) One of the least complicated of the endocrine control systems directly responds to changing blood levels of ions and nutrients. Which of the following describes this mechanism? A) carbohydrate oxidation B) protein synthesis C) catabolic inhibition D) humoral stimulation

23) The major targets of growth hormone are ________. A) bones and skeletal muscles B) the liver and gall bladder C) the adrenal glands D) the blood vessels

24) Which of the following is NOT a parathyroid gland mechanism to maintain adequate levels of blood calcium? A) inhibition of calcitonin synthesis B) increased intestinal absorption of calcium ions C) increased calcium ion reabsorption by the kidneys D) activation of osteoclasts

25) Mineralocorticoid is to aldosterone as glucocorticoid is to ________. A) testosterone B) estrogen C) epinephrine D) cortisol

26) Leptin is secreted by ________. A) adipose cells B) fibroblasts C) goblet cells D) lymphocytes

27) The most important mineralocorticoid regulator of electrolyte concentrations in extracellular fluids is ________. A) cortisol B) insulin C) glucagon D) aldosterone

28) Which of the following is NOT a steroid-based hormone? A) estrogen B) cortisol C) epinephrine D) aldosterone

29) The single most important regulator of calcium levels in the blood is ________. A) thyroid hormone B) gonadotropic hormones C) calcitonin D) parathyroid hormone

30) Cellular responses to hormones that initiate second-messenger systems include ________. A) possible activation of several different second-messenger systems B) hormone binding to intracellular receptors C) cyclic AMP phosphodiesterase formation of an active second messenger D) formation of a specific protein kinase that acts on a series of extracellular intermediates

31) Regulating hormones from the hypothalamus ________. A) enter the hepatic portal system, which feeds the pituitary B) first enter into the hypophyseal portal system C) enter venous circulation and travel to the heart, which pumps the hormone-containing blood to the pituitary D) travel by arteries to the pituitary

32) Adrenocorticotropic hormone (ACTH) ________. A) causes the release of hormones from the adrenal medulla B) is secreted by the posterior pituitary C) is not a tropic hormone D) secretion is regulated by a hypothalamic regulatory hormone

33) Aldosterone ________. A) is secreted by the posterior pituitary B) presence increases potassium concentration in the blood C) production is greatly influenced by ACTH D) functions to increase sodium reabsorption

34) Which organ does NOT produce hormones? A) heart B) spleen C) kidney D) skin

35) In circumstances where the body requires prolonged or increased levels of a hormone, the DNA of target cells will specify the synthesis of more receptors on the surface of the cells of the target organ. This is known as ________. A) a stressor reaction B) sensitivity increase C) up-regulation D) cellular affinity

36) Eicosanoids do NOT include ________. A) leukotrienes B) prostaglandins C) hydrocortisones D) paracrines

37) A man has been told that he is NOT synthesizing enough follicle-stimulating hormone (FSH), and for this reason he may be unable to father a child. Choose the correct statement to explain this problem. A) A hormone made in the anterior pituitary cannot influence fertility. B) The man must be producing progesterone, which inhibits the synthesis of FSH. C) FSH stimulates sperm production in the testes. D) FSH stimulates estrogen secretion by ovarian cells. therefore it is not synthesized by males.

38) Thyroxine is a peptide hormone, but its mechanism is different from other peptide hormones. Which of the following statements is true concerning this difference? A) It is very specific in the cell type it targets. B) It is a stimulant of cellular metabolism and targets all cells. C) It causes positive feedback. D) It does not require a second messenger to cause a response.

39) How do glucocorticoids enable the body to deal appropriately with stress? A) by increasing blood glucose, fatty acid, and amino acid levels and enhancing blood pressure B) by stimulating the pancreas to release insulin C) by releasing the neurotransmitters that prepare the body for the stress response D) by decreasing the heart rate, thus decreasing blood pressure

40) What ion is sometimes used as a second messenger of amino acid-based hormones? A) sodium B) calcium C) iron D) chlorine

41) John tells you that cholesterol is bad and should be eliminated from the diet. You explain to him that cholesterol is important. Which of the following hormones are synthesized from cholesterol? A) testosterone B) thyroxine C) oxytocin D) growth hormone

42) Which hormone has only one known effect: to stimulate milk production by the breasts? A) oxytocin B) estrogen C) progesterone D) prolactin

43) Bisphenol-A (BPA) is an endocrine disruptor that can leach out of certain plastics. It disrupts the normal function of the endocrine system my mimicking estrogen. Which of the following explains how persistent small amounts of BPA in the body can have effects? A) lock-and-key B) up-regulation C) down-regulation D) half-life

44) The parathyroid glands respond to which type of stimulus? A) hormonal B) humoral C) neural D) positive

45) Dave has discovered a new lipid-soluble hormone. Which of the following is true regarding this hormone? A) can be stored in secretory vesicles B) will be bound to a transport protein in the blood C) receptor will be located on the plasma membrane D) will likely act through a second-messenger system

46) During an afternoon class, Lisa starts to feel hungry and worries that her blood sugar level may be dropping. Which hormone is helping to prevent a drop in blood sugar level? A) thyroxine B) glucagon C) insulin D) aldosterone

47) Upon landing at the airport in Lagos, Nigeria, Eric feels wide awake even though the local time is 11pm. Which synthetic hormone supplement could he administer to help adjust to the new time zone? A) glucagon B) insulin C) growth hormone D) melatonin

48) At age 85, Lyle's immune system does not respond to vaccines as well as it did when he was younger. The atrophy of which endocrine gland is likely responsible for this? A) thyroid B) thymus C) adrenal D) anterior pituitary

49) Johanna is significantly shorter than normal for her age. Her doctor recommends treatment with a hormone before her growth plates ossify in her long bones. Which hormone is recommended? A) cortisol B) thyroid stimulating hormone C) parathyroid hormone D) growth hormone

50) As a result of stress the anterior pituitary releases ________, which stimulates release of hormones from the adrenal cortex that retain sodium and water, increase blood sugar, and begin breaking down fats. A) ADH B) ACTH C) growth hormone D) thyroid stimulating hormone