Chapter 45 Hormones And The Endocrine System.doc

Campbell Biology, 11e Chapter 45 Hormones and the Endocrine System 45.1 Multiple-Choice Questions 1) You are dissecting a fish in your biology laboratory section. Your teaching assistant points out a long oval structure and tells you it is an endocrine gland. Which of the following would you then know is a true statement about this structure? A) It secretes a product that is released through a series of ducts. B) The gland's product will only interact with receptors on the cell membrane. C) The gland's product is lipid soluble. D) The gland produces and secretes its product into the blood. 2) In experiments where researchers suspect that a hormone may be responsible for a certain physiological effect, they may cut the neurons leading to the organ where the effect being studied occurs. What is the purpose of cutting these neurons? A) to make sure that the effect is not occurring through actions in the nervous system B) to make sure that the organ being affected cannot function unless the researchers stimulate it with an external electrical probe C) to impair the normal functions of the organ so that the hormonal effect can be more easily studied D) to numb the organ so that it can be probed without inducing pain in the lab animal 3) What is the only type of chemical signal that does not alter the physiology of the animal producing that signal? A) neural B) paracrine C) neuroendocrine D) pheromones 4) Testosterone is an example of a chemical signal that affects the very cells that synthesize it, the neighboring cells in the testis, along with distant cells outside the gonads. Thus, testosterone is an example of ________. I) an autocrine signal II) a paracrine signal III) an endocrine signal A) only I and II B) only II and III C) only I and III D) I, II, and III 5) Prostaglandins are local regulators whose chemical structure is derived from ________. A) oligosaccharides B) fatty acids C) steroids D) amino acids 1 Copyright © 2017 Pearson Education, Inc.

6) Aspirin and ibuprofen both ________. A) inhibit the synthesis of prostaglandins B) inhibit the release of nitric oxide, a potent vasodilator C) activate the paracrine signaling pathways that form blood clots D) stimulate vasoconstriction in the kidneys 7) A cell with membrane-bound proteins that selectively bind a specific hormone is called that hormone's ________. A) secretory cell B) endocrine cell C) target cell D) regulatory cell 8) The steroid hormone aldosterone affects only a small number of cells in the body because ________. A) only target cells are exposed to aldosterone B) only target cells contain aldosterone receptors C) aldosterone is unable to enter nontarget cells D) nontarget cells destroy aldosterone before it can produce any effect 9) Different body cells can respond differently to the same polypeptide hormones because ________. A) different target cells have different sets of genes B) a target cell's response is determined by the components of its signal transduction pathways C) the circulatory system regulates responses to hormones by routing the hormones to specific targets D) the hormone is chemically altered in different ways as it travels through the circulatory system 10) Hormone X activates the cAMP second messenger system in its target cells. The greatest response by a target cell would come from ________. A) applying a molecule of hormone X to the extracellular fluid surrounding the cell B) injecting a molecule of hormone X into the cytoplasm of the cell C) applying a molecule of cAMP to the extracellular fluid surrounding the cell D) injecting a molecule of activated, cAMP-dependent protein kinase into the cytoplasm of the cell 11) When a steroid hormone and a polypeptide hormone exert similar effects on a population of target cells, then ________. A) the steroid and polypeptide hormones must use the same biochemical mechanisms B) the steroid and polypeptide hormones must bind to the same receptor protein C) the steroid hormones affect the synthesis of effector proteins, whereas polypeptide hormones activate effector proteins already present in the cell D) the steroid hormones affect the activity of certain proteins within the cell, whereas polypeptide hormones directly affect the processing of mRNA

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12) Growth factors are local regulators that ________. A) are modified fatty acids that stimulate bone and cartilage growth B) are found on the surface of cancer cells and stimulate abnormal cell division C) bind to cell-surface receptors and stimulate growth and development of target cells D) convey messages between nerve cells 13) Steroid and polypeptide hormones typically have in common ________. A) the building blocks from which they are synthesized B) their solubility in cell membranes C) their requirement for travel through the bloodstream D) their reliance on signal transduction in the cell 14) A cluster of tumor cells that produces and secretes growth factors to induce surrounding cells to grow and divide is showing which type of cell-to-cell signaling? A) autocrine B) paracrine C) endocrine D) neuroendocrine 15) If a portion of the pancreas is surgically removed from a rat and the rat subsequently loses its appetite, one explanation is that the removed portion contains cells that secrete a chemical signal that somehow stimulates appetite. Given this scenario, what type of chemical signaling is occurring? A) autocrine B) paracrine C) endocrine D) neuroendocrine 16) If a biochemist discovers a new molecule, which of the following pieces of data would allow her to draw the conclusion that the molecule is a steroid hormone? I) The molecule is lipid soluble. II) The molecule is derived from a series of steps beginning with cholesterol. III) The molecule acts at a target tissue some distance from where it is produced. IV) The molecule uses a transport protein when in an aqueous solution such as blood. A) only I and III B) only II and IV C) only I, III, and IV D) I, II, III, and IV

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17) Which of the following are similar in structure to cholesterol? I) estradiol II) insulin III) glucocorticoids IV) testosterone V) antidiuretic hormone A) I and II B) I, II, and III C) I, III, and IV D) II and V 18) Polypeptides can have which of the following types of effects? I) autocrine II) paracrine III) endocrine A) only I and III B) only II and III C) only I and II D) I, II, and III 19) Which of the following are properties of steroid hormones? I) Steroid hormones are lipid soluble and easily cross the phospholipid bilayer. II) Steroid hormones usually exert their effects on target cells through membrane receptor proteins. III) Steroid hormones act on cells close to where they were produced. IV) Steroid hormones regulate gene transcription by binding to intracellular receptor proteins. A) I and IV B) I and II C) II and III D) I, II, III, and IV 20) Tadpoles must undergo a major metamorphosis to become frogs. This change includes reabsorption of the tail, growth of limbs, calcification of the skeleton, increase in rhodopsin in the eye, development of lungs, change in hemoglobin structure, and reformation of the gut from the long gut of an herbivore to the short gut of a carnivore. Amazingly, all of these changes are induced by thyroxine. What is the most likely explanation for such a wide array of effects of thyroxine? A) There are many different forms of thyroxine, each specific to a different tissue. B) Different tissues have thyroxine receptors that activate different signal transduction pathways. C) Some tissues have membrane receptors for thyroxine, while other tissues have thyroxine receptors within the nucleus. D) Different releasing hormones release thyroxine to different tissues.

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21) What happens in a cell when adenylyl cyclase is activated? A) cAMP is created B) cAMP is destroyed C) G proteins bind to cAMP D) steroid hormones pass through the lipid bilayer 22) Nitric oxide and epinephrine ________. A) both regulate blood flow B) both function as steroid hormones C) bind the same receptors D) both cause a reduction in the blood levels of glucose 23) Insect hormones and their receptors ________. A) act independently of each other B) are a focus in pest control research C) utilize cell-surface receptors only D) are active independently of environmental cues 24) During mammalian labor and delivery, the contraction of uterine muscles is enhanced by oxytocin. This is an example of ________. A) a negative feedback system B) a hormone that acts in an antagonistic way with another hormone C) a hormone that is involved in a positive feedback loop D) signal transduction immediately changing gene expression in its target cells 25) Which of the following has both endocrine and exocrine activity? A) the pituitary gland B) parathyroid glands C) salivary glands D) the pancreas 26) Analysis of a blood sample from a fasting individual who had not eaten for 24 hours would be expected to reveal high levels of ________. A) insulin B) glucagon C) gastrin D) glucose 27) The steroid hormone that coordinates molting in arthropods is ________. A) ecdysteroid B) glucagon C) thyroxine D) growth hormone

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28) Which of the following statements are correct? I) Hormones often regulate homeostasis through antagonistic functions. II) Hormones of the same chemical class usually have the same function. III) Hormones are secreted by specialized cells usually located in exocrine glands. IV) Hormones are often regulated through feedback loops. A) only II and III B) only I and III C) only III and IV D) only I and IV 29) An example of antagonistic hormones controlling homeostasis is ________. A) thyroxine and parathyroid hormone in calcium balance B) insulin and glucagon in glucose metabolism C) progestins and estrogens in sexual differentiation D) epinephrine and norepinephrine in fight-or-flight responses 30) The relationship between the insect hormones ecdysteroid and PTTH is an example of ________. A) an interaction of the endocrine and nervous systems B) competitive inhibition of a hormone receptor C) how polypeptide-derived hormones have more widespread effects than steroid hormones D) homeostasis maintained by antagonistic hormones 31) Hormones secreted by the posterior pituitary gland are made in the ________. A) cerebellum B) thalamus C) hypothalamus D) anterior pituitary gland 32) Injury localized to the hypothalamus would most likely disrupt ________. A) short-term memory B) coordination during locomotion C) executive functions, such as decision making D) regulation of water balance 33) Which of the following is an example of a simple endocrine pathway? A) control of metabolism by thyroid hormones B) release of secretin by cells of the duodenum in response to acid C) release of antidiuretic hormone from the posterior pituitary gland to regulate water balance D) regulation of growth by the production of growth hormone 34) Portal blood vessels connect two capillary beds found in the ________. A) hypothalamus and thalamus B) anterior pituitary and posterior pituitary C) hypothalamus and anterior pituitary 6 Copyright © 2017 Pearson Education, Inc.

D) posterior pituitary and thyroid gland 35) If a person loses a large amount of water in a short period of time, he or she may die from dehydration. Antidiuretic hormone (ADH) can help reduce water loss through its interaction with its target cells in the ________. A) anterior pituitary B) posterior pituitary C) bladder D) kidney 36) A product of the anterior pituitary gland that causes color changes in its target cells is ________. A) follicle-stimulating hormone (FSH) B) luteinizing hormone (LH) C) thyroid-stimulating hormone (TSH) D) melanocyte-stimulating hormone (MSH) 37) In a lactating mammal, the two hormones that promote milk synthesis and milk release, respectively, are ________. A) prolactin and calcitonin B) prolactin and oxytocin C) follicle-stimulating hormone and luteinizing hormone D) luteinizing hormone and oxytocin 38) Oxytocin and antidiuretic hormone (ADH) are synthesized in the ________ but released from the ________. A) hypothalamus; posterior pituitary B) adenohypophysis; posterior pituitary C) posterior pituitary; anterior pituitary D) hypothalamus; anterior pituitary 39) What would be a likely outcome of a person not consuming enough iodine in their diet? A) high body temperature B) high levels of circulating blood glucose C) reduced cellular metabolism D) stronger muscle contractions 40) Which of the following is the most likely explanation for hypothyroidism in a patient whose iodine level is normal? A) greater production of T3 than of T4 B) hyposecretion of thyroid-stimulating hormone (TSH) C) hypersecretion of thyrotropin-releasing hormone (TRH) D) a decrease in the thyroid secretion of calcitonin

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41) When a person drinks alcohol, the rate of urination increases. Which of the following best accounts for the increase in urination above normal rates? A) Alcohol stimulates the release of thyroid hormones. B) Alcohol inhibits the release of ADH. C) Alcohol inhibits the actions of calcitonin. D) Alcohol stimulates the release of oxytocin which causes more water secretion. 42) Removing which of the following glands would have the most wide-reaching effect on bodily functions of an adult human? A) adrenal glands B) pituitary gland C) thyroid gland D) ovaries (in female) or testes (in male) 43) Glucocorticoids do which of the following? A) promote the immune response B) promote the release of fatty acids C) increase blood glucose levels D) increase insulin production 44) Fight-or-flight reactions include activation of the ________. A) parathyroid glands, leading to increased metabolic rate B) anterior pituitary gland, leading to cessation of gonadal function C) adrenal medulla, leading to increased secretion of epinephrine D) pancreas, leading to a reduction in the blood sugar concentration 45) The amino acid tyrosine is a starting substrate for the synthesis of ________. A) epinephrine B) steroid hormones C) parathyroid hormone D) acetylcholine 46) If the adrenal cortex were surgically removed, an increase in the plasma levels of ________ would likely be observed. A) glucocorticoid hormones B) epinephrine C) adrenocorticotropic hormone (ACTH) D) acetylcholine 47) During a stressful interval, ________. A) thyroid-stimulating hormone (TSH) stimulates the adrenal cortex and medulla to secrete acetylcholine B) increased acid in the duodenum stimulates the S cells to release secretin C) adrenocorticotropic hormone (ACTH) stimulates the adrenal cortex, and neurons of the sympathetic nervous system stimulate the adrenal medulla 8 Copyright © 2017 Pearson Education, Inc.

D) the calcium levels in the blood are increased due to actions of two antagonistic hormones, epinephrine and norepinephrine 48) In response to stress, the adrenal gland promotes the synthesis of glucose from noncarbohydrate substrates via the action of the steroid hormone ________. A) estradiol B) cortisol C) thyroxine D) adrenocorticotropic hormone (ACTH) 49) Melatonin is secreted by the ________. A) hypothalamus during the day B) pineal gland during the night C) autonomic nervous system during the winter D) posterior pituitary gland during the day 50) DES is called an "endocrine disrupting chemical" because it interferes with the endocrine secretions of the ________. A) thyroid gland B) adrenal medulla C) ovaries D) hypothalamus 51) Following a stressful stimulus, the fight-or-flight response will cause ________. A) glucose to be stored in liver cells B) epinephrine to be released from the anterior pituitary C) an increase release of thyroid hormones D) the breakdown of glycogen into glucose 52) Use the figure to answer the following question. Daily injections of progesterone (milligrams) Percentage of rats that carried fetus to birth

Group 1

Group 2

0.25

20

0

100

In an experiment, rats' ovaries were removed immediately after impregnation, and then the rats were divided into two groups. Treatments and results are summarized in the table. The results most likely occurred because progesterone exerts an effect on the ________. A) general health of the rat B) metabolism of the uterus C) gestation period of rats D) number of eggs fertilized

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53) Use the bar graph to answer the following question.

People who suffer from chronic fatigue syndrome (CFS) experience ongoing, debilitating fatigue. In one study, cortisol levels in the saliva during the first hour after waking were measured and compared between CFS patients and people without CFS (controls). The data is summarized in the graph. What can you infer from the data? A) A disruption to thyroid hormone production likely results in decreased cortisol in the saliva. B) Cortisol is lower in CFS patients because they were just woken up. C) The normal elevation in adrenocorticotropic hormone level in waking people is reduced in CFS patients. D) CFS patients are generally more relaxed as demonstrated by their decreased stress response. 54) Osteoporosis is a condition in which the density of bones is decreased so much that the individual is at a higher risk of fractures. The more calcium in the bones, the better the bone density. Which of the following would produce the greatest increase in bone calcium levels? A) calcitonin injection B) calcitonin receptor blocker C) parathyroid hormone injection D) glucagon receptor blocker 55) Predict the effects of a drug that increases adrenocorticotropic hormone (ACTH) synthesis. A) increase in glucocorticoid production B) increase in release of corticotropin-releasing hormone (CRH) C) decrease in cortisol release D) decrease in release of corticotropin-releasing hormone (CRH) 56) People experiencing chronic stress may be more likely to become sick because ________. A) too much thyroid hormone is being produced B) elevated epinephrine concentrations deplete all of the available glucose in the body C) high circulating glucocorticoid can suppress the immune response D) their blood glucose is not being regulated appropriately

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57) Correct and appropriate signal transduction processes are generally under strong selective pressure and are determined by the properties of the molecules involved, the concentrations of signal and receptor molecules, and the binding affinities between signal and receptor. Therefore, a hormone action is very specific in a species at any one point in time. However, there are examples of very diverse functions of a specific hormone between groups of organisms. For example, thyroxin, which is produced in all vertebrates and many invertebrates, can trigger growth, differentiation, metamorphosis, maturation, reproduction, behavior, temperature tolerance, osmoregulation, or seasonal adaptation depending on the organism in which it is produced. What is the most logical explanation for such different responses triggered by thyroxin in organisms? A) The concentration of thyroxin varies in different organisms. Invertebrate organisms do not have as much thyroxin as vertebrate organisms. B) Thyroxin and its receptor molecules have a different binding affinity in different organisms. C) Receptor molecules for thyroxin are located on different tissues in different organisms. D) The function of thyroxine in a particular tissue is determined by the genes that are transcribed by the activated thyroxine receptor. 58) The body's reaction to parathyroid hormone (PTH), raising plasma levels of calcium, can be opposed by ________. A) thyroxine B) epinephrine C) growth hormone D) calcitonin 59) Rapid changes to skin color in many vertebrates is under the control of ________. A) melanocyte-stimulating hormone B) adrenocorticotropic hormone C) thyroxine D) melatonin 1) Which of the following is not an accurate statement? A) Hormones are chemical messengers that travel to target cells through the circulatory system. B) Hormones often regulate homeostasis through antagonistic functions. C) Hormones of the same chemical class usually have the same function. D) Hormones are often regulated through feedback loops. 2) The hypothalamus A) synthesizes all of the hormones produced by the pituitary gland. B) influences the function of only one lobe of the pituitary gland. C) produces only inhibitory hormones. D) regulates both reproduction and body temperature. 3) Growth factors are local regulators that A) are produced by the anterior pituitary. B) are modified fatty acids that stimulate bone and cartilage growth. 11 Copyright © 2017 Pearson Education, Inc.

C) are found on the surface of cancer cells and stimulate abnormal cell division. D) bind to cell-surface receptors and stimulate growth and development of target cells. 4) Which hormone is incorrectly paired with its action? A) oxytocin—stimulates uterine contractions during childbirth B) thyroxine—inhibits metabolic processes C) ACTH—stimulates the release of glucocorticoids by the adrenal cortex D) melatonin—affects biological rhythms and seasonal reproduction 5) What do steroid and peptide hormones typically have in common? A) their solubility in cell membranes B) their requirement for travel through the bloodstream C) the location of their receptors D) their reliance on signal transduction in the cell 6) Which of the following is the most likely explanation for hypothyroidism in a patient whose iodine level is normal? A) greater production of T3 than of T4 B) hyposecretion of TSH C) hypersecretion of MSH D) a decrease in the thyroid secretion of calcitonin 7) The relationship between the insect hormones ecdysteroid and PTTH is an example of A) an interaction of the endocrine and nervous systems. B) homeostasis achieved by positive feedback. C) homeostasis maintained by antagonistic hormones. D) competitive inhibition of a hormone receptor.

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