Deck 16: The Endocrine Glands

Question 1

Which statement concerning a goiter is correct?

A) It is an enlarged thyroid.
B) It always accompanies hypothyroidism.
C) It is present only with iodine-deficient diets.
D) It occurs only when TSH levels are elevated.

Answer 1

A

Question 2

Which is correct with regards to thyroid hormone secretion?

A) The anterior pituitary controls daily regulation while the hypothalamus controls long-term patterns of secretion.
B) TSH causes TRH to be secreted, which, in turn, stimulates T3 and T4 release.
C) Thyroid hormone negatively feedback to the hypothalamus.
D) Control is primarily neural.

Answer 2

A

Question 3

Which statement concerning the synthesis and storage of thyroid hormones is INCORRECT?

A) The "iodine pump" of the follicular cells is important for thyroid hormone production.
B) Thyroid hormones are formed within a much larger molecule called thyroglobulin.
C) Thyroid hormone synthesis is greatly stimulated by the presence of TSH.
D) A one- to two-hour supply of thyroid hormone is stored within the colloid in the lumen of the follicle.

Answer 3

D

Question 4

Hyperthyroidism can be due to all of the following EXCEPT ______________

A) too much TRH
B) too much TSH
C) lack of iodine
D) too much T4 or T3

Question 5

Which statement concerning thyroid hormones is correct?

A) They regulate basal metabolic rate.
B) They are released from the thyroid gland immediately after synthesis.
C) They contain chromium and zinc as structural cofactors.
D) They are tropic.

Question 6

What does NOT happen during thyroid hormone secretion?

A) The follicular cells phagocytize a piece of colloid.
B) T4 and T3 are split off thyroglobulin by lysosomal enzymes within the follicular cell and subsequently diffuse out of the cell into the blood.
C) T4 and T3 are secreted by exocytosis of the colloid that has been internalized by the follicular cells.
D) a and b

Question 7

Which statement concerning thyroid hormones is INCORRECT?

A) They are derivatives of an amino acid.
B) They are produced from tyrosine.
C) They are secreted from parafollicular C cells.

Question 8

Which of the following is NOT an effect of thyroid hormone?

A) increased metabolic rate
B) increased tissue responsiveness to catecholamines
C) increased absorption of iodine from the digestive tract into the blood
D) normal growth

Question 9

Which of the following is NOT a characteristic of thyroid hormone?

A) It increases the overall metabolic rate.
B) It exerts a calorigenic effect.
C) It binds to receptors on the surface of all body cells.
D) It enhances glycogenolysis and lipolysis.

Question 10

Which of the following are NOT plasma proteins to which thyroid hormone is bound in circulation?

A) Albumin
B) gamma globulin
C) thyroxine-binding globulin

Question 11

What happens to most of the secreted T₄?

A) It is phagocytized by target tissues.
B) It is converted into T3 after being peripherally stripped of one of its I atoms.
C) It is the major biologically active form of thyroid hormone at the cellular level.
D) It is split to form two DIT molecules, which are excreted in the urine.

Question 12

Which statement concerning thyroxin is correct?

A) It is formed by coupling one MIT and one DIT within the colloid.
B) It is produced by the C cells of the thyroid gland.
C) It exerts a calorigenic effect.
D) It inhibits thyroid-stimulating immunoglobulin in negative-feedback fashion.

Question 13

Which endocrine gland secretes hormones containing iodine?

A) adrenal cortex
B) adrenal medulla
C) pancreas
D) thyroid

Question 14

Which of the following is NOT characteristic of Graves' disease?

A) It is a symptom is exophthalmos.
B) It is an autoimmune disease.
C) It is caused by a goiter.
D) There is an elevated basal metabolic rate.

Question 15

What does the "iodine pump" refer to?

A) a mechanism whereby target cells extract iodine-containing thyroid hormone from the blood
B) an active transport mechanism that concentrates iodine in the thyroid
C) a mechanism whereby T3 and T4 are released from thyroglobulin and pumped into the circulation
D) a protein-binding process whereby T3 and T4 are pumped throughout the body bound to plasma proteins

Question 16

Which statement concerning TSH is INCORRECT?

A) It is inhibited by thyrotropin-releasing hormone (TRH).
B) It is inhibited by T3 and T4.
C) It promotes hypertrophy and hyperplasia of thyroid cells.

Question 17

Which of the following hormones targets osteoclasts when blood calcium levels are too low,thus causing an increase in the concentration of calcium in the blood?

A) thyroid hormone
B) Cortisol
C) parathyroid hormone
D) Calcitonin

Question 18

Which of the following would NOT decrease thyroid hormone production?

A) a decrease in TSH production
B) an iodine-deficient diet
C) an increase in TRH production
D) inhibition of the iodine pump

Question 19

Which biochemical event does NOT take place during thyroid hormone synthesis?

A) One monoiodotyrosine molecule combines with one diiodotyrosine molecule to form one tri-iodothyronine molecule.
B) Two iodine molecules combine with one tyrosine molecule to form one diiodotyrosine molecule.
C) Two diiodotyrosine molecules combine to form one molecule of thyroxine.
D) Four iodine molecules combine with one tyrosine molecule to form one tetraiodothyronine molecule.

Question 20

Which hormone is NOT produced by the thyroid gland?

A) calcitonin
B) thyroxine
C) parathyroid hormone

Question 21

Which statement concerning adrenocortical hormones is INCORRECT?

A) The glucocorticoids are examples.
B) Some are steroids.
C) They are all controlled primarily by TSH.
D) They are secreted from the outer layer of the adrenal gland.

Question 22

What does the zona glomerulosa of the adrenal cortex secrete?

A) aldosterone
B) cortisol
C) androgens and estrogens
D) epinephrine

Question 23

What would a drop in blood pressure be expected to lead to?

A) increased plasma aldosterone levels
B) increased glucocorticoid levels
C) decreased plasma aldosterone levels
D) decreased glucocorticoid levels

Question 24

Which statement concerning a goiter is NOT correct?

A) It may occur with hyper- and hypothyroidism.
B) It refers to an enlarged thyroid gland.
C) It occurs only in the presence of thyroid-stimulating immunoglobulin.

Question 25

What is not a cause of hypothyroidism?

A) lack of TRH
B) iodine-deficient diet
C) Grave's disease
D) lack of an enzyme necessary for one of the steps in the synthesis and release of thyroid hormone.

Question 26

Which of the following does NOT regulate aldosterone secretion?

A) ACTH
B) the renin-angiotensin system, which is activated by various factors related to a fall in plasma Na+ concentration/ECF volume/arterial blood pressure
C) the direct effect of plasma K+ on the adrenal cortex

Question 27

Which statement is correct for mineralocorticoids?

A) They stimulate gluconeogenesis.
B) They stimulate protein degradation.
C) They act at the kidneys to promote sodium retention and enhance potassium elimination.
D) They contribute to the pubertal growth spurt.

Question 28

What is NOT an action of cortisol?

A) increasing the conversion of glycogen to glucose
B) stimulating gluconeogenesis in the liver
C) increasing protein degradation
D) mobilizing fat from adipose tissue

Question 29

Which of the following symptoms is NOT associated with hyperthyroidism?

A) elevated basal metabolic rate
B) myxedema
C) weakness
D) excessive perspiration

Question 30

Which of the following hormones decreases the concentration of calcium in the blood?

A) thyroxine
B) tri-iodothyronine
C) Calcitonin
D) parathyoid hormone

Question 31

Plasma sodium levels are high in a patient,but his plasma potassium levels are low.As an underlying cause of this condition,what might you expect to find?

A) decreased plasma aldosterone levels
B) decreased plasma parathyroid hormone levels
C) increased plasma aldosterone levels
D) increased plasma parathyroid hormone levels

Question 32

What does an increase in plasma levels of ACTH lead to?

A) increased plasma cortisol levels
B) increased plasma glucagon levels
C) increased plasma vasopressin levels
D) increased plasma parathyroid hormone levels

Question 33

Which statement is correct for aldosterone?

A) It causes conservation of sodium.
B) It facilitates lipolysis.
C) It promotes gluconeogenesis.
D) It is regulated by ACTH.

Question 34

Which two hormones are produced from the same large precursor molecule,pro-opiomelanocortin?

A) aldosterone, cortisol
B) cortisol, androgen
C) cortisol, beta endorphin
D) aldosterone, androgen

Question 35

Hypothyroidism may not occur when?

A) occur secondarily to posterior pituitary failure.
B) occur due to inadequate dietary supply of iodine.
C) be due to failure of the thyroid gland itself.

Question 36

Which statement is correct for aldosterone?

A) It enhances the ability of the kidneys to eliminate excess K+.
B) It directly promotes H2O conservation by the kidneys.
C) Its secretion is encouraged by angiotensin II.
D) It is nonsteroidal.

Question 37

A woman is found to have the following symptoms: a large goiter,muscle weakness,excessively emotional and irritable disposition,extreme weight loss,a constant feeling of being too warm in normal-temperature rooms,and bulging eyes.What is the provisional diagnosis?

A) myxedema
B) Cushing's disease
C) Conn's syndrome
D) Graves' disease

Question 38

What is associated with hyperthyroidism?

A) poor resistance to cold
B) myxedema
C) slow speech, poor memory
D) exophthalmos

Question 39

What is the most abundant and physiologically important adrenal sex hormone?

A) aldosterone
B) cortisol
C) dehydroepiandrosterone
D) estradiol

Question 40

What it the precursor to testosterone?

A) aldosterone
B) cortisol
C) dehydroepiandrosterone
D) estradiol

Question 41

What is the major factor that promotes increased secretion of cortisol from the adrenal cortex?

A) low Na+ concentration in the extracellular fluid
B) physical and emotional stress
C) angiotensin II
D) increased blood amino acid concentration

Question 42

Which of the following is NOT an effect of epinephrine?

A) It constricts the respiratory airways.
B) It elevates the concentration of blood sugar.
C) It stimulates glycogenolysis in skeletal muscles.
D) It stimulates hepatic gluconeogenesis.

Question 43

When a student experiences psychological and emotional stress,what won't they secrete at higher levels?

A) GRH
B) ACTH
C) cortisol

Question 44

Which statement is NOT true for dehydrorpiandrosterone?

A) It is the most abundant adrenal androgen.
B) It is responsible for the development and maintenance of the female sex drive.
C) It is controlled by the gonadotropic hormones.

Question 45

Which statement is NOT true of cortisol?

A) It has immunosuppressive effects.
B) It is an anti-inflammatory.
C) It results in facultative potassium resorption.

Question 46

Which of the following is characteristic of Conn's syndrome?

A) K+ increase in the blood
B) Na+ depletion
C) hypertension

Question 47

Which hormone exhibits a marked diurnal variation in secretion?

A) aldosterone
B) cortisol
C) thyroid hormone
D) epinephrine

Question 48

Which of the following is NOT the action of Glucocorticoids?

A) carbohydrate conservation
B) protein degradation
C) increased metabolic rate
D) mobilization of fats for energy

Question 49

What is NOT true of glucocorticoids?

A) decreased gluconeogenesis and glycogenolysis
B) increased fat mobilization
C) increased breakdown of muscle proteins

Question 50

Because aldosterone encourages K⁺ secretion into the urine,what does conditions in which excess aldosterone is secreted result in?

A) hyponatremia.
B) hypokalemia.
C) hypotension.
D) idiopathic atrophy.

Question 51

Which statement is correct for adrenocorticotropic hormone?

A) It is a tropic hormone secreted by the adrenal cortex.
B) It stimulates the production of androgens by the testes.
C) It is controlled in part by CRH from the hypothalamus.

Question 52

Which statement is correct for catecholamines?

A) They are secreted by the adrenal cortex.
B) They reinforce the parasympathetic nervous system.
C) They are important in the maintenance of blood pressure.
D) They promote glycogen storage.

Question 53

Which statement concerning adrenal androgens is NOT true

A) It is normally secreted only in males, whereas adrenal estrogens are secreted in females.
B) It is normally secreted in both males and females, but in insufficient amounts to cause masculinization.
C) It is responsible for the female sex drive.

Question 54

Which of the following is NOT characteristic of Cushing's syndrome?

A) hypernatremia
B) hyperglycemia
C) muscle weakness and fatigue
D) poor wound healing

Question 55

When catecholamines are secreted from the adrenal medulla,what is this a response to?

A) increased secretion of ACTH from the anterior pituitary.
B) direct sympathetic nervous system stimulation.
C) decreased androgen secretion from the adrenal cortex.
D) a tropic hormone secreted by the pituitary.

Question 56

Which of the following is characteristic of the adrenogenital syndrome?

A) precocious pseudopuberty in prepubertal boys
B) development of female-type external genitalia in male fetuses
C) hirsutism in adult females
D) a and c

Question 57

Which statement is NOT true for epinephrine?

A) It is secreted by the adrenal cortex
B) It is cosecreted with norepinephrine.
C) It reinforces sympathetic nervous system activity.

Question 58

Of the hormones secreted by the adrenal gland,which does NOT promote an increase in the blood glucose level?

A) aldosterone
B) cortisol
C) epinephrine

Question 59

Which statement is NOT true for cortisol?

A) It is the primary mineralocorticoid.
B) Its excess is responsible for Cushing's syndrome.
C) It increases blood glucose, blood fatty acid, and blood amino acid levels.

Question 60

Which of the following is NOT seen in Addison's disease?

A) marked Na+ loss in the urine
B) lowered blood glucose levels
C) K+ retention
D) protein mobilization

Question 61

Increased levels of which hormone would NOT result in increased blood fatty acid levels?

A) glucagon
B) growth hormone
C) insulin
D) epinephrine

Question 62

Which of the following does NOT characterize diabetes mellitus?

A) increased glucose utilization due to excessive glucose availability
B) polyuria due to the osmotic effect of glucose in the urine
C) acidosis due to the ketosis accompanying abnormal fat metabolism
D) polydipsia due to dehydration

Question 63

What does NOT characterize the post absorptive state?

A) There is a substantial reduction in blood glucose concentration compared to the absorptive state.
B) Gluconeogenesis occurs.
C) Glucose-sparing occurs.
D) Insulin secretion is reduced.

Question 64

Which statement is INCORRECT for gluconeogenesis?

A) It refers to the conversion of amino acids into glucose.
B) It results in an increase in blood glucose.
C) It is stimulated by insulin.

Question 65

Which statement is INCORRECT for glycogenesis?

A) It results in a storage form of glucose.
B) It is stimulated by glucagon.
C) It is stimulated by insulin.

Question 66

Which of the following is NOT an outcome of insulin secretion?

A) increased GLUT-4 mobilization
B) promoting glucose uptake by neural tissue
C) inhibiting lipolysis
D) promoting glycogenesis

Question 67

Which of the following nutrient molecules,when in excess quantities,can NOT be stored in adipose tissue as triglycerides?

A) fat-soluble vitamins
B) glucose
C) amino acids

Question 68

Which statement concerning somatostatin is INCORRECT?

A) Somatostatin is produced by the hypothalamus.
B) Somatostatin is produced by the pancreatic D cells.
C) Somatostatin inhibits growth hormone secretion.
D) Somatostatin is released in response to a fall in blood glucose and blood amino acids.

Question 69

Which of the following is NOT characteristic of the general adaptation syndrome?

A) mobilization of energy reserves
B) conservation of water and sodium
C) increased systemic vasodilation

Question 70

Which statement is INCORRECT for blood sugar levels?

A) They must remain within normal range because the brain needs a constant supply of sugar.
B) They increase in response to glucagon secretion.
C) They increase in response to glycogenesis.

Question 71

Which of the following hormones is NOT secreted in response to stress?

A) cortisol
B) epinephrine
C) insulin
D) aldosterone

Question 72

Which statement is true during the absorptive state?

A) glycogenolysis is occurring.
B) fats are the primary energy source.
C) glucose is the main energy source.
D) amino acid degradation is occurring.

Question 73

Which statement is correct for insulin?

A) It facilitates the entry of glucose into brain tissue.
B) It promotes glucose output by the liver.
C) It lowers blood glucose levels.
D) It facilitates the entry of glucose into brain tissue and lowers blood glucose levels.

Question 74

Secretion of which hormone is stimulated by an increase in blood glucose?

A) glucagon
B) cortisol
C) growth hormone
D) insulin

Question 75

Which statement is INCORRECT for insulin?

A) It promotes the insertion of additional glucose transporters in the plasma membranes of insulin-dependent cells.
B) It stimulates glycogenesis and inhibits glycogenolysis.
C) Its secretion is increased in response to a fall in blood glucose concentration.

Question 76

Which pituitary hormone increases the concentration of blood sugar?

A) glucagon
B) insulin
C) cortisol
D) growth hormone

Question 77

Which statement concerning the adrenomedulla hormones is INCORRECT?

A) Epinephrine accounts for 80 percent of adrenomedullary catecholamine output.
B) Epinephrine and norepinephrine are stored within chromaffin granules in the adrenomedullary cells.
C) Epinephrine and norepinephrine have about equal affinities for all the adrenergic receptor types.
D) Epinephrine is at least 10 times more potent than norepinephrine at beta 2 receptors.

Question 78

Which of the following does NOT stimulate insulin secretion?

A) elevated blood amino acid concentration
B) gastrointestinal hormones
C) a fast-food hamburger
D) starvation

Question 79

Which statement is correct for insulin?

A) It facilitates the transport of glucose into the glucose-dependent brain cells.
B) It increases blood glucose levels to ensure adequate nourishment of the brain.
C) It promotes fat storage in the body.
D) It is stimulated by lowered blood glucose.

Question 80

Where does glycogenesis occur?

A) liver
B) brain
C) working muscle
D) nonworking muscle