Exam 2: Endocrine Practice Questions

Question 1

What is the primary function of the endocrine system?

Answer 1

produce and secrete hormones to regulate physiological processes in order to maintain homeostasis

Question 2

How do hormones travel through the body to reach their target organs?

Answer 2

Humorally through the bloodstream

Question 3

What are the three major classes of hormones?

Answer 3

peptide, steroid, amine derived

Question 4

Which gland is known as the “master gland” and why?

Answer 4

hypothalamus; releases many tropic hormones that produce a cascade of other hormones throughout the body

Question 5

How do peptide hormones differ from steroid hormones in terms of solubility and receptor location?

Answer 5

• peptide hormones: dissolved in plasma; receptors located on the cell membrane
• steroid hormones: not soluble in blood (bound to carrier proteins); receptors located in the cytoplasm or nucleus of a cell

Question 6

What hormone is secreted by the pineal gland and what is its major function?

Answer 6

melatonin; regulates sleep cycles based on light available (less light = more melatonin produced)

Question 7

Which hypothalamic hormones regulate the anterior pituitary?

Answer 7

Growth hormone-releasing hormone (GHRH); Corticotropin-releasing factor (CRF); Gonadotropin-releasing hormone (GNRH); Thyrotropin-releasing hormone (TRH); Dopamine

Question 8

What are the two hormones released by the posterior pituitary, and what are their primary functions?

Answer 8

• oxytocin: initiates smooth muscle contraction in the uterus and breasts; contractions, let-down reflex
• vasopressin (ADH): increases collecting duct water permeability

Question 9

How does oxytocin affect the uterus and lactation?

Answer 9

by initiating smooth muscle contraction in the uterus (contractions during labor) and breasts (let down reflex)

Question 10

What is the role of vasopressin (ADH) in kidney function?

Answer 10

Vasopressin increases water and sodium retention in the nephron

Question 11

Which hormone promotes milk production in the breast tissue?

Answer 11

Prolactin

Question 12

What is the function of growth hormone, and what tissues does it primarily target?

Answer 12

Growth hormone stimulates the secretion of insulin-like growth factors from the liver to promote bone and soft tissue growth

Question 13

How does adrenocorticotropic hormone (ACTH) affect the adrenal cortex?

Answer 13

ACTH increases the production of cortisol in the adrenal cortex

Question 14

What are the target organs of thyroid-stimulating hormone (TSH)?

Answer 14

Thyroid gland

Question 15

What are the primary hormones secreted by the thyroid gland?

Answer 15

triiodothyronine, thyroxine, calcitonin

Question 16

How does calcitonin regulate calcium levels in the body?

Answer 16

calcitonin promotes calcium uptake into bones (promoting osteoblast activity and inhibiting osteoclast activity)

Question 17

Which hormone regulates plasma calcium levels by increasing calcium resorption from bones?

Answer 17

Parathyroid hormone (PTH)

Question 18

What hormones are produced by the thymus gland, and what is their role in immunity?

Answer 18

thymosin, thymopoietin

Question 19

How does atrial natriuretic peptide (ANP) from the heart affect kidney function?

Answer 19

ANP acts as a vasodilator and inhibits renin release which ultimately lowers blood pressure

Question 20

How do insulin-like growth factors from the liver contribute to growth?

Answer 20

promote bone and tissue growth

Question 21

What is the primary function of angiotensinogen, and which gland produces it?

Answer 21

angiotensinogen, when activated to be angiotensin, releases aldosterone to increase water and sodium retention to increase blood pressure

Question 22

What hormones are involved in digestion, and which organs secrete them?

Answer 22

angiotensinogen, gastrin, cholecystokinin, secretin, insulin, glucagon, somatostatin, pancreatic polypeptide

Question 23

Which hormones are produced by the pancreas, and how do they regulate blood glucose levels?

Answer 23

• insulin: secreted by beta cells in the pancreas after a meal; signals GLUT transporters to migrate to cell membranes to take up glucose
• glucagon: secreted by alpha cells in the pancreas; signals the liver to release glucose into the blood

Question 24

How do aldosterone and cortisol differ in their function?

Answer 24

• aldosterone: controls sodium and water retention
• cortisol: manages stress, influences metabolism, and regulates blood sugar levels

Question 25

How do epinephrine and norepinephrine contribute to the fight-or-flight response?

Answer 25

a-receptor: epinephrine binds in intestinal blood vessels > constriction B-receptor: epinephrine binds in skeletal blood vessels > dialation

Question 26

Which hormone stimulates red blood cell production in the bone marrow?

Answer 26

erythropoietin

Question 27

How does 1,25-Dihydroxy-vitamin D3 regulate calcium absorption?

Answer 27

cholesterol + UV radiation > vitamin D3 > calcitriol which has a synergistic effect with PTH to increase blood calcium levels

Question 28

What is the function of vitamin D3 produced by the skin?

Answer 28

Vitomin D3 is converted to calcitriol to increase blood calcium levels

Question 29

Which hormones have important functions in the reproductive system?

Answer 29

androgens, inhibin, estrogen, progesterone, relaxin, chorionic somatomammotropin, chorionic gonadotropin

Question 30

How does negative feedback regulate hormone secretion in the endocrine system?

Answer 30

when downstream hormones reach a ceratin concentration they can inhibit upstream glands

Question 31

Which hormones are involved in stress responses, and how do they interact?

Answer 31

cortisol, epinephrine, norepinephrine

Question 32

How does insulin lower blood glucose levels, and which hormone has the opposite effect?

Answer 32

insulin promotes GLUT receptors to migrate to cell membranes in order to bring glucose into the cell for cellular respiration

Question 33

What is the primary target of thyroid hormones, and how do they affect metabolism?

Answer 33

primary target: tissues; increase metabolism by increasing the rate of cellular activity and energy usage

Question 34

How do glucocorticoids, such as cortisol, regulate metabolism and immune responses?

Answer 34

increasing blood glucose levels; suppress immune response

Question 35

How do adipose tissue hormones influence metabolism and energy storage?

Answer 35

regulate appetite and fat burning

Question 36

What are the effects of leptin on appetite and metabolism?

Answer 36

high leptin levels signal satiety leading to decreased appetite and increased metabolism

Question 37

How do hormones influence bone growth and maintenance?

Answer 37

- calcitonin: when blood calcium levels are high; increases osteoblast activity and decreases osteoclast activity - PTH/calcitriol: when blood calcium levels are low; decreases osteoblast activity and increases osteoclast activity

Question 38

What endocrine disorders are associated with hormone imbalances?

Answer 38

- congenital diabetes insipidus: abnormal vasopressin receptor > shortens receptor half-life > can't reabsorb glucose/water - familial hypercalcemia: abnormal calcium sensor in parathyroid > fails to respond to increasing plasma calcium levels > high blood calcium

Question 39

How do endocrine glands differ from exocrine glands?

Answer 39

- endocrine: release hormones directly into the bloodstream - exocrine: release secretions through ducts to body's external environment