Chapter 44 The Endocrine System Exam Prep

Biology, 12e (Raven)

Chapter 44 The Endocrine System

1) Your general practitioner considers your unusual set of symptoms, and says, "You seem to have a problem with maintaining homeostasis in your body." Which type of specialist might the doctor refer you to? (Check two.)

A) hematologist

B) endocrinologist

C) neurologist

D) osteologist

E) opthamologist

F) obstetrician-gynecologist

2) A ________ is a regulatory molecule that is secreted into the blood by an endocrine gland.

A) metabolite

B) hormone

C) peptide

D) G protein

E) neurotransmitter

3) A hormone is a regulatory molecule that is secreted into the blood by an endocrine gland. What is wrong with this definition?

A) Endocrine glands are the target of these molecules, not the source.

B) It does not apply to this type of molecule in plants.

C) The molecules do not serve a regulatory role.

D) The definition is completely correct as stated.

4) You are a professor supervising first year medical students. One student is examining the adrenal gland of his cadaver. "Wow!" he exclaims, "This person must have had an endocrine problem. Their adrenal gland lacks any kind of duct connecting it to the bloodstream. The hormones could only have oozed out." How do you respond?

A) "That makes their adrenal gland similar to an exocrine organ."

B) "Do you see signs of adrenal insufficiency, such as low fat stores or muscle degeneration?"

C) "That's normal. The hormones ooze out and diffuse into nearby capillaries, which is why endocrine glands are sometimes called 'ductless glands'."

D) "Look carefully and you will see the nerves that transport the hormones into the bloodstream."

5) Some intercellular regulatory molecules that exert only very local effects are called ________ regulators.

A) sympathetic

B) exogeneous

C) merocrine

D) endocrine

E) paracrine

Sometimes the most practical way to do an experiment is not to perform it in an animal, but to look at cell responses in culture. Cells from mice, humans, and other mammals have been used to establish cell culture lines that have been very important for research. You are studying a novel water-soluble mouse hormone. You know cell culture can be a practical model to reveal protein function, so you apply the hormone to yeast cells, but nothing happens. 

6) What is a likely explanation for why nothing happened in your experiment?

A) Yeast have a cell wall, so the molecule cannot pass through the cell membrane as it would in mice.

B) Water-soluble hormones are lipids, not proteins.

C) You need to apply the hormone in large amounts to see an effect.

D) Yeast may lack the receptor required for the hormone to act.

7) How could you improve your experiment?

A) Apply the hormone to mouse cell culture.

B) Apply the hormone at a concentration of 0.5M.

C) Hydrolyze the hormone before application.

D) Add ATP as a cofactor.

8) The ________ lobe of the pituitary gland appears fibrous because it contains axons originating from hypothalamic neurons.

A) anterior

B) posterior

C) superior

D) inferior

E) medial

9) The anterior pituitary gland is controlled by which three types of signals? (Check three.)

A) direct axonal connections from the hypothalamus

B) negative feedback from its own hormones

C) negative feedback from hormones secreted by the thyroid, adrenal cortex, and gonads

D) positive feedback from its own hormones

E) positive feedback from hormones secreted by the pancreas, heart, and skin

F) releasing hormones secreted by the hypothalamus

10) There is a molecule in black licorice that inhibits an enzyme which normally limits activation of mineralocorticoid receptors. Thus, overconsumption of licorice can mimic the effect of excess aldosterone. What would be the result?

A) infertility in men

B) hypertension (high blood pressure) due to insufficient potassium in the blood

C) excessive body hair

D) low blood pressure due to excessive potassium in the blood

11) A novel disease causes destruction of the adrenal glands. If a patient with this disease failed to receive aldosterone replacement therapy, what would result?

A) death

B) diminished cognitive function

C) infertility in both men and women

D) poor blood sugar regulation

12) The islets of Langerhans located in the ________ secrete both insulin and glucagon.

A) liver

B) pituitary

C) thalamus

D) kidney

E) pancreas

13) Ecdysone and juvenile hormone regulate molting and ________ in insects.

A) metamorphosis

B) sexual behavior

C) body shape

D) egg production

14) Oxytocin is a peptide hormone that causes uterine contractions in childbirth and stimulates milk secretion from nipples. Do men have oxytocin?

15) Women often receive synthetic oxytocin to induce childbirth or augment contractions. What is an important consideration about the use of synthetic oxytocin?

A) It is impossible to mimic its chemical structure, so it may act on other receptors and cause side effects.

B) The synthetic form does not travel down motor neurons, so it is less effective than the natural form.

C) It can be difficult to get the levels just right, so uterine contractions can be too strong.

D) If you fail to simultaneously provide synthetic G protein, the hormone is ineffective.

16) A couple visits a fertility clinic to determine the basis of their difficulty in conceiving a child. They are surprised to hear they will both be tested for levels of two of the same hormones, which play roles in the ovarian cycle and sperm production. Which hormones are they?

A) adrenocorticotropic hormone (ACTH) and corticotropin-releasing hormone (CRH)

B) insulin and glucagon

C) oxytocin and luteinizing hormone (LH)

D) follicle-stimulating hormone (FSH) and luteinizing hormone (LH)

17) The use of bovine growth hormone (BGH) to increase milk yield in dairy cows is highly controversial. What other hormone is regularly added to milk, yet causes little controversy?

A) vitamin A

B) vitamin D

C) MSG

D) preservatives

18) What is the primary function of the hormone ADH?

A) regulates biological rhythms

B) mediates adaptation to long term stress

C) stimulates bone breakdown

D) conserves water by stimulating its reabsorption from urine

E) inhibits loss of calcium from bone

19) What is a primary function of growth hormone?

A) initiates stress response

B) raises blood glucose level

C) lowers blood glucose level

D) stimulates bone growth

E) inhibits loss of calcium from bone

20) What is a primary function of the hormone calcitonin?

A) initiates stress response

B) raises blood glucose level

C) lowers blood glucose level

D) stimulates bone growth

E) inhibits loss of calcium from bone

21) Lampreys completely lack parathyroid glands. Suggest why these glands may be important for other vertebrates, but not for jawless fish.

A) Because they are parasitic, lampreys get plenty of calcium from their hosts.

B) Living in the ocean, they are surrounded by large amounts of sodium, chloride, and magnesium ions.

C) Jawless fish employ a different system than other vertebrates to regulate blood sugar.

D) Since they have a cartilaginous skeleton but not true bone, they have less need to regulate calcium levels.

22) Which hormone helps with adaptation to long term stress?

A) glucocorticoids

B) epinephrine

C) insulin

D) glucagon

E) melatonin

23) Which hormone lowers blood glucose levels?

A) glucocorticoids

B) epinephrine

C) insulin

D) glucagon

E) melatonin

24) Which hormone raises blood glucose levels?

A) glucocorticoids

B) epinephrine

C) insulin

D) glucagon

E) melatonin

25) At the breakfast table, your roommate says, "Oops! I forgot to take my melatonin last night. I'd better take it now." How do you respond?

A) "Good idea — you don't want your bones to get brittle."

B) "Be sure not to take too much, or your blood sugar could get dangerously low."

C) "Don't take it now — it regulates biological rhythms, and is normally high at night and low during the day."

D) "Don't take it after a meal — it promotes the 'fight-or-flight' response, not 'rest-and-digest'."

26) Which hormone sets the body's basal metabolic rate?

A) estrogen

B) insulin

C) norepinephrine

D) cortisol

E) thyroxin

27) The hormones epinephrine and norepinephrine constitute the "alarm" response of the body to stress. What secretes these hormones?

A) pancreas

B) thyroid gland

C) adrenal medulla

D) pineal gland

E) anterior pituitary gland

28) What is an example of a molecule that can act as both a neurotransmitter and a hormone?

A) estrogen

B) progesterone

C) thyroxine

D) norepinephrine

E) insulin

29) Which of the following is a paracrine regulator that affects almost every organ in the body?

A) insulin

B) testosterone

C) prostaglandin

D) gonadotropin

E) epinephrine

30) Which of the following hormones exerts its action by interacting with a receptor at the cell surface?

A) insulin

B) cortisol

C) testosterone

D) estrogen

E) progesterone

31) Which hormone is NOT produced by the anterior pituitary gland?

A) prolactin

B) luteinizing hormone

C) calcitonin

D) growth hormone

32) Why does consumption of alcohol stimulate urination?

A) It stimulates ADH secretion.

B) It inhibits ADH secretion.

C) It stimulates vasopressin.

D) It stimulates oxytocin.

E) It inhibits aldosterone.

33) What hormone stimulates the milk-ejection reflex?

A) antidiuretic hormone

B) oxytocin

C) vasopressin

D) parathyroid hormone

E) aldosterone

34) Hormones of the posterior pituitary gland are transported to the hypothalamus by what unusual route?

A) the limbic system

B) blood vessels

C) axons

D) the lymphatic system

E) the hypopituitary shunt

35) What hormone stimulates milk production in mammals?

A) aldosterone

B) melatonin

C) prolactin

D) luteinizing hormone

E) growth hormone

36) Which of the following are examples of gonadotropins?

A) prolactin and oxytocin

B) follicle-stimulating hormone and oxytocin

C) luteinizing hormone and estrogen

D) prolactin and estrogen

E) follicle-stimulating hormone and luteinizing hormone

37) Nonpolar hormones can pass through the intestinal cell membrane without being digested, and therefore can be taken orally. Which of the following hormones are available as pills?

A) insulin and growth hormone

B) thyroid hormone and steroid hormones

C) calcitonin and insulin

D) insulin and steroid hormones

E) calcitonin and thyroid hormone

38) Which is NOT an effect of the hormonal products of the adrenal medulla?

A) accelerate heartbeat

B) stimulate synthesis of glycogen

C) increase blood pressure

D) reduce blood flow to the skin and digestive organs

E) increase blood sugar

39) Which one of the following is a glucocorticoid important in both gluconeogenesis (glucose produced from amino acids) during starvation and anti-inflammation?

A) aldosterone

B) cortisol

C) glucagon

D) insulin

E) prolactin

40) Which of the following hormones is NOT produced by the adrenal gland?

A) epinephrine

B) cortisol

C) prolactin

D) aldosterone

E) norepinephrine

41) Which two hormones interact to maintain normal levels of blood glucose?

A) cortisone and testosterone

B) epinephrine and norepinephrine

C) glucagon and insulin

D) LH and FSH

E) oxytocin and vasopressin

42) When the body's blood glucose level rises above normal, which of the following hormones is produced?

A) glucagon

B) epinephrine

C) insulin

D) norepinephrine

E) prolactin

43) Which of the following conditions is not associated with diabetes?

A) elevated levels of blood glucose

B) lowered production of insulin by the pancreas

C) reduced body cell sensitivity to insulin

D) defects in pituitary gland function

E) careful diet and exercise measures are required to balance blood sugar levels

44) The right atrium secretes atrial natriuretic hormone (ANH), which stimulates the kidneys to excrete salt and water into the urine. ANH acts antagonistically to what other hormone?

A) cortisol

B) aldosterone

C) glucagon

D) thyroxine

E) progesterone

45) Which of the following is NOT an example of a sex steroid hormone?

A) estrogen

B) progesterone

C) prolactin

D) testosterone

E) estradiol

46) Which of the following hormones regulates metamorphosis and molting in insects?

A) melatonin

B) ecdysone

C) estrogen

D) somatostatin

E) trypsin

47) Which two systems in the human body are devoted exclusively to the regulation of organ function?

A) endocrine and circulatory systems

B) respiratory and circulatory systems

C) nervous and circulatory systems

D) nervous and endocrine systems

E) respiratory and nervous systems

48) Choose the hormone that is NOT correctly matched with its chemical category.

A) polypeptides—ADH

B) steroid—estradiol

C) amine—FSH

D) glycoprotein—LH

E) steroid—testosterone

49) Which statement below does NOT correctly describe paracrine regulation?

A) Paracrine regulatory molecules include cytokines and growth factors.

B) Nitric oxide can function either as a neurotransmitter or a paracrine regulatory molecule.

C) Endothelin and bradykinin are paracrine molecules that control blood vessel constriction and dilation.

D) Paracrine molecules are released into the circulatory system to affect distant tissues.

E) Platelet-derived growth factor and insulin-like growth factor are both paracrine regulatory molecules.

50) Choose the hormone that is NOT correctly matched with the endocrine gland that secretes it.

A) adrenal cortex—aldosterone

B) pancreas—insulin

C) pineal gland—melatonin

D) adrenal medulla—cortisol

E) posterior lobe of pituitary gland—oxytocin

51) The cells of the anterior lobe of the pituitary gland secrete many hormones. From the following list select the hormone that is NOT secreted from the anterior lobe of the pituitary.

A) growth hormone

B) prolactin

C) follicle-stimulating hormone

D) melanocyte-stimulating hormone

E) antidiuretic hormone

52) Large or polar hormones cannot enter a cell directly. Which of the following molecules can act as a second messenger for such hormones?

A) catecholamine

B) cyclic AMP

C) epinephrine

D) norepinephrine

E) calcitonin

53) Which statement does NOT correctly describe hormones that can directly enter a cell?

A) Steroid hormones can enter directly into cells because of their hydrophobic makeup.

B) Water-soluble hormones can enter directly into cells because of their nonpolar makeup.

C) Steroid hormones dissolve poorly in the plasma and are transported to target cells via special protein carriers.

D) Once these hormones enter a cell, they bind to a cytoplasmic receptor and travel as a complex to the nucleus, or they may bind to the receptor after entering the nucleus.

54) Which of the following does NOT correctly describe antidiuretic hormone?

A) It regulates water turnover in the mammalian kidney.

B) ADH secretion is stimulated by high blood osmolarity.

C) It ultimately acts to reabsorb more water.

D) It exerts it effects via the cAMP pathway.

E) It does not involve the use of aquaporin molecules.

55) Which hormone is secreted by alpha cells of the pancreas in response to hypoglycemia?

A) glucagon

B) insulin

C) glucose

D) cortisol

E) glycogen

56) Which hormone is most similar in amino acid structure to chicken vasotocin?

A) antidiuretic hormone

B) aldosterone

C) angiotensin II

D) growth hormone

E) oxytocin

57) Which is the best explanation for how ibuprofen works?

A) It thins the blood to relieve joint pain.

B) It inhibits cyclooxygenase-2, which is needed to produce prostaglandins.

C) It activates cyclooxygenase-2, which then produces more prostaglandins.

D) It down-regulates the production of substance P.

E) It activates cyclooxygenase-2, which promotes healing of tissue.

58) Which of the following is likely to occur after drinking three alcoholic beverages?

A) Increased urination due to alcohol activating antiduretic hormone production.

B) Decreased urination due to alcohol activating aldosterone production.

C) Increased urination due to alcohol inhibiting antidiuretic hormone production.

D) Decreased urination due to alcohol inhibiting antidiuretic hormone production.

E) Increased urination due to alcohol inhibiting aldosterone production.

59) Which of the following is NOT a function of oxytocin?

A) pair bonding

B) milk-ejection reflex

C) milk production

D) uterine contractions

60) Which of the following hormones has the fewest targets?

A) growth hormone

B) melatonin

C) oxytocin

D) thyroid-stimulating hormone

E) testosterone

61) Which of the following is NOT a function of parathyroid hormone?

A) It increases calcium production in the liver.

B) It increases calcium absorption across the intestine.

C) It increases reabsorption of Ca2+ in the kidney.

D) It stimulates osteoclasts to dissolve CaPO4 crystals in bone.

62) Which of the following features distinguishes all hormones from neurotransmitters?

A) Hormones require large concentrations to have an effect, while neurotransmitters require only low concentrations.

B) A hormone affects reproductive functions, while neurotransmitters control all other processes.

C) Hormones travel via the blood to a target tissue, while neurotransmitters cross the synaptic cleft to a postsynaptic cell.

D) Hormones are steroids, while neurotransmitters are amino acids.

63) What is the difference between the endocrine system and the autonomic nervous system?

A) The endocrine system employs chemical signals only, while the autonomic nervous system involves a combination of electrical and chemical signals.

B) The autonomic nervous system promotes "fight or flight" functions, while the endocrine system promotes "rest and digest" functions.

C) Norepinephrine is produced by the autonomic nervous system, while epinephrine is produced by the endocrine system.

D) The axons of neurons of the endocrine system travel a shorter distance than those of the autonomic nervous system.

64) If blood transports hormones throughout the body, how do they communicate with specific targets?

A) Special gateway valves in the blood vessels direct hormones to their target tissues.

B) Special carrier proteins "walk" along microtubule tracts to deliver the hormones to their targets.

C) Axonal pathfinding mediates the delivery of hormones to their specific targets.

D) Only target tissues have receptors that allow them to receive the signal.

65) True or False: Hormones must be present at high concentrations to elicit an effect.

66) True or False: A molecule can act as both a neurotransmitter and a hormone.

67) True or False: The brain controls organ system function only through direct contact with sympathetic or parasympathetic nerves.

68) Which are endocrine organs? (Check all that apply.)

A) adenohypophysis

B) adrenal gland

C) cochlea

D) hypothalamus

E) ileum

F) lymph node

G) neurohypophysis

H) ovary

J) pancreas

K) pineal gland

L) salivary gland

M) sebaceous gland

N) spleen

O) testis

P) thyroid gland

69) Why don't hormones build up in the body over time?

A) They are secreted from the body by exocrine glands.

B) They are filtered out of the blood by lymph tissues.

C) They do, but target tissues become desensitized over time.

D) They are degraded by enzymes in the target tissue.

70) You are studying a disease caused by insufficient levels of a specific peptide hormone, and characterize mutations in several genes that can lead to the disease. Your startup company can only afford to pursue one gene product as a possible therapy. Which would you choose?

A) Gene A — a transcription factor.

B) Gene B — an enzyme that activates the hormone by cleaving its inactive precursor.

C) Gene C — the hormone itself.

D) Gene D — a kinase that acts downstream of the hormone.

The basic categories of hormones are peptide or proteins, steroids, and amino acid derivatives. The chemical properties of each hormone type determine some of its functional properties and how it must interact with receptors to signal to the cell.

71) A new hormone is discovered. Tests reveal that it is small, hydrophilic, and degraded by a protease. What type of hormone is it?

A) peptide

B) amino acid derivative

C) steroid

D) glucocorticoid

E) prostaglandin

72) Is it likely that a small, hydrophilic hormone can cross the cell membrane?

73) What are the three main categories of hormones? (Check three.)

A) adrenergic

B) amino acid derivative

C) anabolic

D) catabolic

E) cytosolic

F) peptide / protein

G) steroid

74) You are researching an "orphan disease" with no available treatment. Your lab develops a drug that mimics a lipophilic hormone thought to be lacking in the disease, and you are looking for a pharmaceutical company to partner with to run a clinical trial. Based on the reaction from each team, which would you choose to work with?

A) Company A: "What you've developed is wonderful, but we'll need to develop a delivery system to get the drug across the cell membrane."

B) Company B: "Your new drug seems very promising. Do you know which G-protein coupled receptor it binds to?"

C) Company C: "We're interested in developing this drug - it could really help people. Do you know which genes the hormone regulates?"

75) You are an attending physician supervising a new resident. Together, you decide to treat a patient with a steroid drug. The resident administers the drug and watches the patient anxiously. "It's not working," he mutters. How do you respond?

A) "You're right, it doesn't seem to be working. Let's increase the dose, since we need to achieve high steroid levels in the blood."

B) "Why don't you go on your rounds and come back? Steroid hormones need several hours to work, since they regulate gene expression. Transcription and translation take time."

C) "We forgot to administer the carrier protein to get the drug across the cell membrane. We can add that now."

D) "Let's grab a cup of coffee and then check again. Activating the G-protein coupled receptor and its downstream kinase cascade can take several minutes."

76) You are scheduled to give a seminar to your fellow med school students, and have chosen to speak about the pituitary. What important points will you include? (Check all that apply.)

A) The posterior pituitary is derived from the brain, while the anterior pituitary is not.

B) The anterior pituitary is derived from the brain, while the posterior pituitary is not.

C) The pituitary is a compound endocrine gland.

D) Each half of the pituitary secretes one important hormone.

E) Some pituitary hormones have sex-specific effects.

F) If there is too little iodine in the diet, the pituitary can grow into a goiter.

G) The pituitary is responsible for producing at least nine major hormones.

77) ACTH stands for adrenocorticotropic hormone, but it is produced in the anterior pituitary. What is the basis of this name?

A) It is expressed most highly in tropical climates.

B) It stimulates the adrenal cortex.

C) It signals to the kidneys to reabsorb water.

D) It stimulates appetite by acting on the cerebral cortex.

78) What stimulates the production of adrenocorticotropic hormone (ACTH)?

A) GHRH

B) CRH

C) CIH

D) ADH

79) Which are important components of the communication between the hypothalamus and anterior pituitary? (Check all that apply.)

A) ADH and oxytocin

B) capillaries

C) fibrous pituitary stalk

D) GHIH, PIF, and MIH

E) hormones

F) hypothalamohypophyseal portal system

G) transport of hormones down axons

H) TRH, CRH, GnRH, and GHRH

80) Which are important components of the communication between the hypothalamus and posterior pituitary? (Check all that apply.)

A) ADH and oxytocin

B) capillaries

C) fibrous pituitary stalk

D) GHIH, PIF, and MIH

E) hormones

F) hypothalamohypophyseal portal system

G) transport of hormones down axons

H) TRH, CRH, GnRH, and GHRH

81) Your doctor returns with your lab results and looks grave. "I'm afraid," she says, "you seem to have a problem with your hypophysis." What do you say?

A) "Doctor, right now I'm interested in results, not testable ideas about how things work!"

B) "Well, that's only responsible for one or two hormones, so it should be easy to treat."

C) "Am I going to need insulin shots?"

D) "Is it the posterior? Neurological problems run in my family."

Cushing's syndrome causes weight gain, excessive sweating, and muscle weakness. It can result from either the production of abnormally high levels of cortisol by the body, or overuse of glucocorticosteroid drugs. You are an endocrinologist working with a Cushing's syndrome patient. She is on hormonal birth control pills and takes an occasional ibuprofen.

82) What lab tests would you order to find the source of the problem?

A) cortisol, LH, and FSH

B) None -- the birth control pills include corticosteroid hormones. She should switch to another form of birth control.

C) cortisol, ACTH, and CRH

D) cortisol and ACTH

83) Results from lab tests reveal abnormally high endogenous hormone levels, and you suspect a possible tumor. What regions will you ask the MRI technician to focus on?

A) hypothalamus, anterior pituitary, and adrenal cortex

B)  adrenal cortex only

C)  hypothalamus and posterior pituitary

D) anterior and posterior pituitary

84) You have a pediatric patient with signs of excessive growth, or gigantism. Initial tests reveal abnormally high levels of growth hormone. What other hormone disruptions might be the primary cause of his symptoms? (Check all that apply.)

A) high GHIH

B) low GHIH

C) high GHRH

D) low GHRH

E) high GnRH

F) low GnRH

85) A middle-aged female patient complains of changes to her face. Her cheekbones and eyebrows have become more prominent, and her jaw is growing. You suspect acromegaly, a disorder caused by excessive growth hormone. She had no growth abnormalities in her youth. What do you suspect is the most likely cause of her problem?

A) a tumour of the pineal gland

B) congenital mutation of the GH regulatory region

C) a tumour of the anterior pituitary

D) a tumour of the posterior pituitary

E) menopause

86) Increased use of MRI technology has resulted in a surprising medical dilemma. Scans used for early detection of tumors often reveal benign internal growths that would otherwise have gone undetected, called incidentalomas. This creates the problem of determining whether the growths are harmful without performing needless surgeries. Assume that you have found a pituitary incidentaloma in one of your patients. What blood tests could you perform to determine whether it is causing dysfunction? (Check all that apply.)

A) adrenococrticotropic hormone (ACTH)

B) luteinizing hormone (LH)

C) antidiuretic hormone (ADH)

D) melanocyte-stimulating hormone (MSH)

E) calcitonin

F) melatonin

G) follicle stimulating hormone (FSH)

H) oxytocin

J) glucagon

K) prolactin (PRL)

L) growth hormone (GH)

M) thyroid-stimulating hormone (TSH)

N) insulin

O) thyroxine

87) Your friend is concerned because although she has never been pregnant, her breasts are producing milk. When she went to the doctor, he sent her to the MRI lab for a brain scan. She was too embarrassed to ask the doctor why. What do you tell her?

A) "They were actually scanning your thyroid gland, not your brain. Are you getting enough iodine in your diet?"

B) "The MRI technician must have mixed up your patient records. He should have done a thoracic scan instead."

C) "LH and FSH from the posterior pituitary stimulate milk production. The doctor wants to rule out excess levels of estrogen in the pituitary stalk."

D) "Prolactin from the anterior pituitary stimulates milk production. The doctor probably wants to rule out a pituitary tumor."

88) True or False: The thyroid requires negative feedback to prevent overgrowth.

89) True or False: If Ca+2 levels in the blood are too low, hormones from the parathyroid gland can induce bones to dissolve and release calcium.

90) Blood glucose levels must be carefully maintained within a narrow window. What endocrine organ is responsible for this task?

A) pancreas

B) pineal gland

C) pituitary gland

D) parathyroid gland

91) What strategy does the body use for blood glucose homeostasis?

A) release of hormones by the brain

B) energy stores in bone allow for quick glucose release

C) glucose usage by the brain is shut down when necessary

D) the action of two antagonistic effectors

92) When a diabetic injects insulin, what does this accomplish?

A) promotes glucose release from cells, raising blood glucose

B) promotes uptake of glucose into cells, lowering blood glucose

C) promotes hydrolysis of glycogen, raising blood glucose

D) improves the ability of the body to sense blood glucose levels

93) Estrogen and testosterone are steroid hormones that differ by only a few atoms. The different receptor binding properties those differences confer allow the hormones to do what during development?

A) Cause differential maturation of the prefrontal cortex during late adolescence.

B) Cause a slight increase in muscle mass in females versus males.

C) Make females naturally attracted to pink and males to blue.

D) Control development of all sex-specific physical traits including sex organs, body hair, and breasts.

94) Atrial natriuretic hormone (ANH) stimulates the kidneys to excrete salt and water in the urine. Why does it make sense that the heart is the source of ANH?

A) The heart is a major endocrine organ that releases several hormones.

B) ANH helps regulate blood pressure, which is sensed by distension of the heart atria.

C) The heart is conveniently close to the hypothalamus.

D) Secretion of hormones by the heart makes it easy for them to enter the bloodstream.

95) What nonendocrine organ produces erythropoietin, which stimulates red blood cell production in the bone marrow?

A) kidneys

B) skin

C) heart

D) pituitary

E) liver

Many insecticides target insect hormones such as juvenile hormone or ecdysone to disrupt development. This is preferable to simply killing the insect with more broadly-acting toxins.

96) Your cat has fleas! You look at the ingredients in the flea control ointment, and see that it contains methoprene, a juvenile hormone analog. What does this accomplish?

A) prevents flea larvae from maturing

B) kills juvenile fleas

C) reinvigorates the cat's immune system, to repel the fleas

D) forces juvenile fleas to mature early, disrupting development of reproductive organs

97) What is a benefit of targeting hormone signaling rather than a generic cellular housekeeping process in insects?

A) It is water soluble.

B) It works very quickly.

C) It disrupts the entire population in the area.

D) It is specific to insects and less toxic to mammals.

98) G protein coupled receptors are a large class of receptors that bind hormones as well as other signaling molecules, neurotransmitters, and even odorants. They are a major target of pharmaceutical drugs for various disorders. Typically, the drug acts as an antagonist, blocking the binding site on the GPCR. Why is the receptor a more attractive drug target than the G protein activated downstream? (Check all that apply.)

A) It is easier to target molecules from the outside of the cell membrane, because getting drugs into the cell can be difficult.

B) Interfering with the G protein would require getting a drug across several membranes into the cell's nucleus.

C) The "G-protein" is not really a protein but just a GTP molecules, which is too small to be a possible drug target.

D) Since GPCRs are so widespread and perform many roles in the body, targeting G proteins used by multiple GPCRs would create side-effects beyond the targeted physiological function.

E) Since the GPCRs bind a variety of unique ligands, their structures are varied enough to be able to create specific targeted drugs for certain pathways.

99) Beta-blockers are a class of drugs that target beta-adrenergic receptors, blocking the action of epinephrine and norepinephrine. These drugs are used to treat heart conditions, hypertension, glaucoma, and migraine headaches and are also used off-label to alleviate stage fright in performers. Since the beta-adrenergic receptor is a GPCR, what intracellular event is prevented by the use of a beta-blocker?

A) a protein kinase cascade, initiated by the receptor's intracellular kinase domain

B) release of an activated G protein subunit bound to GTP

C) transport of the receptor-hormone complex into the cell and the nucleus, where it would regulate transcription

D) a protein phosphatase cascade, initiated by the receptor's intracellular phosphatase domain

100) Ultimately, the signal from a peptide hormone is typically conveyed to the effectors in the cell via the transfer of what molecular moiety?

A) nucleotide

B) NO (nitric oxide)

C) H2O

D) phosphate group

E) amino acid

101) To exert its effects on gene regulation in a cell, a steroid hormone must interact with a variety of proteins and cell structures along the way. Check the box for each interaction partner.

A) carrier protein

B) microtubules

C) plasma membrane

D) hormone receptor

E) nuclear membrane

F) GPCR