Deck 16: The Digestive System

Question 1

The primary energy source for the body during the postabsorptive state is glucose.

Answer 1

False

Question 2

Sympathetic stimulation inhibits the secretion of insulin.

Answer 2

True

Question 3

Aldosterone and cortisol are both considered to be essential for life.

Answer 3

False

Question 4

ACTH stimulates the zona fasciculata and zona reticularis to a far greater extent than it stimulates the zona glomerulosa of the adrenal cortex.

Question 5

Hyperparathyroidism is characterized by hypercalcaemia and hyperphosphataemia.

Question 6

PTH is the most important hormone in the control of calcium metabolism.

Question 7

Insulin secretion is decreased and glucagon secretion is increased in response to a fall in blood glucose concentration.

Question 8

Stress is the primary stimulus for mineralocorticoid secretion.

Question 9

The symptoms of aldosterone hypersecretion include hypernatraemia, hyperphosphataemia, and hypertension.

Question 10

Elevated blood amino acid levels stimulate the secretion of both insulin and glucagon, even though they exert opposite effects on blood amino acid concentration.

Question 11

Epinephrine and norepinephrine exert identical effects in all tissues.

Question 12

The thyroid gland stores enough thyroid hormone to supply the body's needs for several months.

Question 13

Once a structural protein is synthesized, it remains a part of the cell for the duration of the cell's life.

Question 14

Norepinephrine is released from sympathetic nerve terminals, whereas epinephrine is the most abundant secretory product of the adrenal medulla.

Question 15

PTH enhances the rapid movement of calcium from the bone fluid into the plasma.

Question 16

An increase in plasma PO₄ concentration forces a reduction in plasma Ca²⁺ as a result of the inverse relationship between plasma PO₄ and Ca²⁺ levels.

Question 17

Thyroid hormone is stored within the colloid attached to thyroglobulin.

Question 18

Calcitonin decreases plasma Ca²⁺.

Question 19

Hypothyroidism can occur even though the thyroid gland is perfectly normal.

Question 20

Adrenal androgens are normally secreted only in males, whereas adrenal estrogens are secreted only in females.

Question 21

Both Type I and Type II diabetes must be treated by regular insulin injections.

Question 22

Epinephrine is more potent than norepinephrine at beta-2 adrenergic receptors.

Question 23

Thyroid-stimulating immunoglobulin stimulates both the secretion and growth of the thyroid similar to TSH.

Question 24

Most of the secreted T₃ is converted into T₄ outside the thyroid gland.

Question 25

Thyroid-stimulating hormone is produced by the thyroid gland.

Question 26

Cortisol is secreted by the zona glomerulosa, aldosterone by the zona fasciculata, and sex hormones by the zona reticularis.

Question 27

Obesity can precipitate overt Type II diabetes mellitus in individuals genetically predisposed.

Question 28

Excess TSH stimulation causes hypertrophy in the thyroid gland.

Question 29

The greater the physical stress and compression to which a bone is subjected, the greater the rate of bone deposition.

Question 30

Both calcitonin and PTH are produced in the follicle cells of the thyroid gland.

Question 31

The adrenocortical hormones cortisol and aldosterone are peptide hormones.

Question 32

Because of the thyroid hormone's growth-promoting effects, excessive growth is one outcome of excess thyroid hormone secretion in children.

Question 33

Plasma phosphate concentration is not as tightly controlled as plasma calcium concentration.

Question 34

The "iodine pump" actively transports hormone-bound iodine from the thyroid gland into the circulation.

Question 35

The blood glucose level is the primary controlling factor of insulin secretion.

Question 36

Myxoedema is associated with hypersecretion of thyroid hormones.

Question 37

Gluconeogenesis and glycogenolysis in the liver play a major role in maintaining a constant blood glucose level between meals.

Question 38

The presence of a goitre is always indicative of hyperthyroidism.

Question 39

Insulin increases glucose transport into all tissues.

Question 40

Thyroglobulin is found in the cytosol of the thyroid follicular cells.

Question 41

The adrenal medulla is actually a modified part of the sympathetic nervous system.

Question 42

Vitamin D deficiency is the cause of rickets.

Question 43

Triiodothyronine and tetraiodothyronine are produced by the C-cells of the thyroid gland.

Question 44

Cortisol is the primary mineralocorticoid.

Question 45

The absorptive state is directed by an increase in insulin secretion.

Question 46

PTH increases plasma Ca²⁺ and decreases plasma PO₄.

Question 47

Cushing's syndrome is characterized by hyperglycaemia, muscle weakness, "moon-face," and "buffalo hump."

Question 48

Insulin is secreted by the alpha cells of the islets of Langerhans.

Question 49

Protein-bound Ca²⁺ is the form of calcium that is important in neuromuscular excitability.

Question 50

Osteoblasts communicate to osteoclasts via osteoprotegerin.

Question 51

All forms of diabetes mellitus are characterized by a lack of pancreatic insulin secretion.

Question 52

In people who work during the day, cortisol levels in the plasma are normally higher in the morning than at night.

Question 53

Vitamin D is actually a hormone that increases calcium absorption in the intestine.

Question 54

Insulin and glucagon secretion are both stimulated by an increase in blood amino acid concentration.

Question 55

One of the primary functions of cortisol secretion at normal physiological levels is its anti-inflammatory action.

Question 56

Vitamin D must be provided entirely by dietary sources.

Question 57

Over 99 percent of the circulating thyroid hormone is bound to plasma proteins.

Question 58

Amino acids can be converted to glucose, whereas fatty acids cannot.

Question 59

The presence of vitamin D is necessary for PTH to exert its effect on promoting intestinal Ca²⁺ absorption.

Question 60

Plasma Ca²⁺ concentration is one of the most tightly controlled variables in the body.

Question 61

Which of these statements does NOT apply to parathyroid hormone?

A)It causes localized dissolution of bone.
B)It conserves Ca²⁺ by the kidney.
C) It promotes urinary excretion of PO₄.
D) It directly stimulates Ca²⁺ absorption from the intestine.

Question 62

Which statement correctly applies to the adrenomedullary hormones?

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 63

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 goitre.
D) There is an elevated basal metabolic rate.

Question 64

Which of these statements is a characteristic of calcitonin?

A)Its production is stimulated by TSH.
B)Its production stimulated by calcium.
C) It is secreted by the C-cells of the thyroid gland.
D) It is stored in the colloid of the thyroid follicles.

Question 65

What stimulates the release of PTH from the parathyroid gland?

A)calcitonin from the anterior pituitary gland
B)low levels of calcium ions in the blood
C) TSH from the anterior pituitary gland
D) low levels of glucose in the blood

Question 66

Which of the following 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 67

Which of the following characterizes Type I but not Type II diabetes mellitus?

A)hyperglycaemia
B)lack of insulin
C) polyuria and polydipsia
D) usually manageable by dietary control and weight reduction without the necessity of insulin injections

Question 68

The parathyroid gland secretes parathyroid hormone and calcitonin.

Question 69

Which statement provides a characteristic of a goitre?

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.

Question 70

Which of the following does NOT stimulate insulin secretion?

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

Question 71

Which statement is NOT true for dehydroepiandrosterone?

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.
D) It is a precursor of testosterone.

Question 72

Which of these descriptions applies to the "iodine pump"?

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 73

Which of these actions is performed by 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 gluconeogenesis in liver tissues.

Question 74

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 75

Which of these statements is correct with respect 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 provides negative feedback to the hypothalamus.
D) Its control is primarily neural.

Question 76

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 77

Which of these hormones does the zona glomerulosa of the adrenal cortex secrete?

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

Question 78

Which of these hormones influences increased protein degradation?

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

Question 79

What it the precursor to testosterone?

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

Question 80

Which of these statements does NOT apply to epinephrine?

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