18.9 ADRENAL GLANDS

Question 1

WHERE ARE THE ADRENAL GLANDS LOCATED?

Answer 1

lies superior to each kidney in the retroperitoneal space

Question 2

what kind of shape are adrenal glands

Answer 2

flattened pyramidal shape
adult 3-5 cm in hight, 2-3 cm width, less than 1 cm thick

Question 3

during embryonic development the adrenal glands differentiate into 2 structurally and functionally distict regions which are called what?

Answer 3

1. Large (peripherally located adrenal cortex) 80-90% of the gland
2. small (centrally located adrenal medulla)

Question 4

what kind of tissue covers the gland

Answer 4

connective tissue
highly vascularized

Question 5

what kinds of hormones does the adrenal cortex produce

Answer 5

steroid hormones

Question 6

complete loss of adrenocorticol hormones leads to

Answer 6

death due to dehydration and electrolyte imbalances in a few days to a week

Question 7

the adrenal medulla produces which 3 catecholamine hormones

Answer 7

norepinephrine, epinephrine , small amount of dopamine

Question 8

adrenal cortex subdivided into 3 zones (zona glomerulosa, zona fasciculata, zona reticularis) which is the inner, middle and outer zone?

Answer 8

inner- zona reticularis
middle - zona fasciculata
outer - zona glomerulosa

Question 9

in the outer zone (zona glomerulosa) its cells are closely packed and arranged in spherical clusters and arched columns, which hormones do they secrete?

Answer 9

mineralocorticoids - affect mineral homeostasis

Question 10

the middle zone (zona fasciculata) is the widest and consists of cells arranged in long straight columns, which hormones do they secrete

Answer 10

glucocorticoids - affect glucose homeostasis

Question 11

inner zone (zona reticularis) cells are arranged in branching cords and synthesize small amounts of

Answer 11

weak androgens - steroid hormones that have masculinizing effects

Question 12

what is the major mineralcorticoid?

Answer 12

aldosterone

Question 13

aldosterone regulate homeostasis of which 2 mineral ions

Answer 13

sodium ions
potassium ions
helps adjust BP and blood volume

Question 14

what do glucocorticoids regulate?

Answer 14

metabolism and resistance to stress

Question 15

3 hormones included in glucocorticoids

Answer 15

corticosterone
cortison
cortisol

Question 16

which zone are the 3 hormones secreted by in the adrenal gland?

Answer 16

zona fasciculata

Question 17

which is the most abundant hormone out of the 3 (cortisol, corticosterone, cortisone)

Answer 17

cortisol - 95% of glucocorticoid activity

Question 18

glucocorticoid effects

Answer 18

1. protein breakdown - in muscle fibres - which increases the liberation of amino acids into bloodstream which may be used by body cells for synthesis of proteins or for ATP production
2. glucose formation - after being stimulated by glucocorticoids liver cells can convert amino acids or lactic acid to glucose
   3.lipolysis - stimulate lipolysis - breakdown of triglycerides and release of fatty acid from adipose tissue to blood
3. resistance to stress - make blood vessels more sensitive to other hormones that cause vasoconstriction - ba raised
   5.anti-inflammatory effects - inhibit WBC’s , retard tissue repair - slows wound healing
4. depression of immune responses - high doses can depress immune responses - prescribed for organ transplant recipients to retard tissue rejection by immune system

Question 19

low levels of glucocorticoids (mainly cortisol) stimulate neurosecretory cells in the hypothamalum to secrete

Answer 19

corticotropin0releasing hormone

Question 20

inner region of the adrenal gland - adrenal medulla is

Answer 20

a modified sympathetic ganglion of the autonomic nervous system

Question 21

hormone producing cells

Answer 21

chromaffin cells

Question 22

2 major hormones synthesized by the adrenal medulla

Answer 22

epinephrine and norepinephrine

Question 23

do the chromaffin cells produce an equal amount of the 2 hormones?

Answer 23

no
epinephrine 80%
norepinephrine 20%