Chapter 18 The Endocrine System

anatomy and physiology II

The three stages of the stress response or general adaptation syndrome, in order of occurrence, are what, what, and what.

fight or flight response, resistance reaction and exhaustion

What is the major integrating link between the nervous and endocrine systems, acts as an endocrine gland itself, and helps control the stress response?

the hypothalamus

Down-regulation makes a target cell what sensitive to a hormone while up-regulation makes a target cell what sensitive to a hormone8.

less, more

T/F

If the effect of two or more hormones acting together is greater than the sum of each acting alone, then the two hormones are said to have a permissive effect.

F

T/F

In the direct gene activation method of hormone action, the hormone enters the target cell and binds to an intracellular receptor. The activated receptor-hormone complex then alters gene expression to produce the protein that causes the physiological responses that are characteristic of the hormone.

T

Which of the following comparisons are true?

(1) Nerve impulses produce their effects quickly; hormonal responses generally are slower.

(2) Nervous system effects are brief; endocrine system effects are longer lasting.

(3) The nervous system controls homeostasis through mediator molecules called neurotransmitters; the endocrine system works through mediator molecules called hormones.

(4) The nervous system can stimulate or inhibit the release of hormones; some hormones are released by neurons as neurotransmitters.

(5) Neurotransmitters transmit impulses directly; hormones must bind to receptors on or in target cells in order to exert their effects.

(b) 1, 2, 3, and 4

Insulin and thyroxine arrive at an organ at the same time. Thyroxine causes an effect on the organ but insulin does not. Why?

(a) Insulin is a lipid-soluble hormone and thyroxine is not.

(b) the target cells in the organ have up-regulated for thyroxine
(c ) thyroxine is a local hormone and insulin is a circulating hormone

(d) thyroxine inhibits the action of insulin

(e) the organ’s cells have receptors for thyroxine but not for insulin

(e) the organ’s cells have receptors for thyroxine but not for insulin

Which of the following is not a category of water-soluble hormones?

(a) peptides

(b) amines

(c) eicosanoids

(d) steroids

(e) proteins

(d) steroids

Place in correct order the action of a water-soluble hormone on its target cell.

(1) Adenylate cyclase is activated, catalyzing the conversion of ATP to cAMP.

(2) Enzymes catalyze reactions that produce a physiological response attributed to the hormone.

(3) The hormone binds to a membrane receptor.

(4) Activated protein kinases phosphorylate cellular proteins.

(5) The hormone-receptor complex activates G proteins.

(6) Cyclic AMP activates protein kinases.

(a) 3,5,1,6,4,2

Hormones

(1) generally utilize negative feedback mechanisms to regulate their secretion;

(2) will only affect target cells far removed from the hormone-producing secretory cells

(3) must bind to transport proteins in order to circulate in the blood

(4) may be released in low concentrations but can produce large effects in the target cells because of amplification

(5) can regulate the responsiveness of the target tissue by controlling the number of receptor sites for the hormone

(e) 1, 4, and 5

The pituitary gland

(1) is located in the cribriform plate of the ethmoid bone

(2) is linked to the hypothalamus by the infundibulum

(3) has a posterior portion that contains axon terminals from hypothalamic neurosecretory cells

(4) produces releasing and inhibiting hormones

(5) has a vascular connection with the hypothalamus known as the hypophyseal portal system

(c ) 2, 3, and 5

The class of adrenal gland hormones that provides resistance to stress, produces anti-inflammatory effects, and promotes normal metabolism to ensure adequate quantities of ATP is

(a) glucocorticoids

(b) mineralocorticoids

(c ) androgens

(d)catecholamines

(e) gonadocorticoids

(a) glucocorticoids

What increases blood Ca2+ level?

parathormone

What increases blood glucose level?

-human growth hormone

-epinephrine

-norepinephrine

-cortisol

What decreases blood Ca2+ level?

calcitonin

What decreases blood glucose level?

insulin

What initiates and maintains milk secretion by the mammary glands?

prolactin

What regulates the body’s biological clock?

malatonin

What stimulates sex hormone production; triggers ovulation?

luteinizing hormone

What augments fight-or-flight responses?

epinephrine and norepinephrine

What regulates metabolism and resistance to stress?

cortisol

What helps control water and electrolyte homeostasis?

-aldosterone

-antidiuretic hormone

What suppresses release of FSH?

inhibin

What stimulates growth of axillary and pubic hair?

androgens

What promotes T cell maturation?

thymosin

What regulates oxygen use, basal metabolic rate, cellular metabolism, and growth and development?

-thyroxine

-tri-iodothyronine

What stimulates protein synthesis, inhibits protein breakdown, stimulates lipolysis, and retards use of glucose for ATP production?

human growth hormone

What inhibits water loss through the kidneys?

-antidiuretic hormone

-aldosterone

What stimulates egg and sperm formation?

follicle-stimulating hormone

What enhances uterine contractions during labor; stimulates milk ejection?

oxytocin

What stimulates and inhibits secretion of anterior pituitary hormones?

hypothalamic regulating hormones

What increases skin pigmentation when present in excess?

melanocyte-stimulating hormone

What stimulates synthesis and release of T3 and T4?

thyroid-stimulating hormone

What local hormones are involved in inflammation, smooth muscle contraction, blood flow, and inflammation?

prostaglandins

What hormone-secreting cells release both ACTH and MSH hormones?

corticotrophs

What hormone-secreting cells release TSH hormones?

thyrotrophs

What hormone-secreting cells release glucagon hormones?

alpha cells of pancreatic islet

What hormone-secreting cells release PTH hormones?

chief cells

What hormone-secreting cells release glucocorticoids hormones?

zona fasciculata cells

What hormone-secreting cells release calcitonin hormones?

parafollicular cells of thyroid gland

What hormone-secreting cells release insulin hormones?

beta cells of pancreatic islet

What hormone-secreting cells release androgens hormones?

zona reticularis cells

What hormone-secreting cells release progesterone hormones?

ovary

What hormone-secreting cells release FSH and LH hormones?

gonadotrophs

What hormone-secreting cells release epinephrine and norepinephrine hormones?

chromaffin cells

What hormone-secreting cells release hGH hormones?

somatotrophs

What hormone-secreting cells release testosterone hormones?

testes

What hormone-secreting cells release mineralocorticoids hormones?

zona glomerulosa cells

What hormone-secreting cells release thyroxine and triiodothyronine hormones?

follicular cells of thyroid gland

What hormone-secreting cells release PRL hormones?

lactotrophs

What endocrine disorder produced the problem of hyposecretion of insulin or down-regulation of insulin receptors?

diabetes mellitus

What endocrine disorder produced the problem of hypersecretion of hGH before closure of epiphyseal plates?

giantism

What endocrine disorder produced the problem of hyposecretion of thyroid hormone that is present at birth?

congenital hypothyroidism

What endocrine disorder produced the problem of hypersecretion of glucocorticoids?

Cushing’s syndrome

What endocrine disorder produced the problem of hyposecretion of hGH before closure of epiphyseal plates?

pituitary dwarfism

What endocrine disorder produced the problem of hypersecretion of epinephrine and norepinephrine?

pheochromocytomas

What endocrine disorder produced the problem of hypersecretion of hGH after closure of epiphyseal plates?

acromegaly

What endocrine disorder produced the problem of hyposecretion of glucocorticoids and aldosterone?

Addison’s disease

What endocrine disorder produced the problem of hyposecretion of ADH?

diabetes insipidus

What endocrine disorder produced the problem of hypersecretion of melatonin?

seasonal affective disorder

What endocrine disorder produced the problem of hyposecretion of thyroid hormone in adults?

myxedema

What endocrine disorder produced the problem of hyperthyroidism, an autoimmune disease?

Grave’s disease