Unit 5 - Endocrine Physiology

Question 1

steroid hormone

Answer 1

lipid soluble (lipophilic) - can dissolve through plasma membrane & enter cell

• bind to receptors in the nucleus of their target cells.
• cortisol

Question 2

non-steroid hormones

Answer 2

water soluble (hydrophilic) - cannot dissolve through plasma membrane
attach to a receptor on the membrane
- insulin, FSH

Question 3

Target cell activation depends on 3 things:

Answer 3

1. blood levels of the hormone
2. relative number of receptors on target cell
3. affinity of those receptors for the hormone

Question 4

Up regulation

Answer 4

• target cells form more receptors in response to hormone

- ex. oxytocin (promotes contractions of uterine smooth muscle) receptors increase during the 3rd trimester of pregnancy

Question 5

Down regulation

Answer 5

target cells lose receptors in response to the hormone

Question 6

Name 6 anterior pituitary hormones that are well known:

Answer 6

1. FSH - follicle stimulating
2. LH - leutinizing
3. prolactin
4. TSH - thyroid stimulating
5. ACTH - adrenocorticotropic
6. growth hormone

Question 7

adrenal gland

Answer 7

outer part - cortex

inner part - medulla

Question 8

posterior pituitary hormones

Answer 8

vasopressin

oxytocin

Question 9

anterior pituitary hormones

Answer 9

follicle stimulating hormone (FSH)
leutinizing hormone (LH)
growth hormone (GH)
thyroid stimulating hormone (TSH)
adrenocorticotropin hormone (ACTH)
prolactin

Question 10

Which gland produces iodine containing hormones? What are they called?

Answer 10

Thyroid
Triiodothyronine (T3)
Thyroxine (T4)
Both are non-steroid hormones

Question 11

bone resorption

Answer 11

dissolves bones / removal
puts more Ca2+ in blood plasma
from the parathyroid 
parathyroid hormone (PTH)
osteoclasts

Question 12

High Ca2+ in plasma

Answer 12

thyroid C cells release Calcitonin

they trigger osteoBLASTS to take up Ca2+ & form new bone

Question 13

What hormones & vitamin are involved in calcium homeostasis?

Answer 13

1. Calcitonin - thyroid / if Ca2+ is too high
2. Parathyroid hormone - parathyroid / if Ca2+ is too low
3. Vitamin D -

Question 14

bone deposition

Answer 14

formation of bone

osteoblasts involved

Question 15

humoral stimuli

Answer 15

hormones secreted in direct response to changing blood levels of ions & nutrients

Question 16

hormonal stimuli

Answer 16

release of hormones in response to hormones produced by other endocrine organs

Question 17

neural stimuli

Answer 17

ANS efferent nerve fibers stimulate hormone release

- preganglionic sympathetic NS fibers stimulate the adrenal medulla

Question 18

Thyroid hormones

Answer 18

Both produced by thyroglobulin & iodine

1. T3
2. T4
3. calcitonin (produced by C Cells)

Question 19

Adrenal gland

Answer 19

Cortex has 3 layers:

1. zona glomerulosa (outer most part) - mineral corticoids
   - – mainly aldosterone
2. zona fasciculata (middle layer) - glucocorticoids
   - – cortisol
3. zona reticularis (inner layer) - gonadocorticoids
   - — androgens

Question 20

zona fasciculata

Answer 20

middle part of adrenal cortex

secretes glucocorticoids – cortisol

Question 21

glucocorticoids

Answer 21

zona fasciculata

• cortisol - help resist stress
• stimulate gluconeogenesis
• inhibits glucose uptake by many tissues, making it available for the brain
• stimulates protein degradation
• facilitates lipolysis
• anti-inflammatory agent

Question 22

gonadocorticoids

Answer 22

zona reticularis

- source of testosterone for men/ estrogen for women

Question 23

mineralcorticoids

Answer 23

zona glomerulosa

- aldosterone

Question 24

Pancreas

Answer 24

alpha cells secrete glucagons

beta cells secrete insulin

Question 25

diabetes insidious caused by:

Answer 25

deficiency in vasopressin/ADH

Question 26

The term used to describe the presence of glucose in the urine is

Answer 26

glycosuria

Question 27

catecholamines

Answer 27

released by adrenal medulla

• epinephrine
• norepinechrine

Question 28

How does Vit D help with Ca2+ levels?

Answer 28

• promotes absorption in intestine

- decrease Ca2+ loss in urine

Question 29

Pancreas - what is exocrine & what is endocrine?

Answer 29

Exocrine - secretes watery, alkaline solution & digestive enzymes thru pancreatic duct into digestive tract lumen

Endocrine - 1-2% of mass; islets of Langerhans

1. beta cells - (60% of islet mass) synthesize & secrete hormone INSULIN
2. alpha cells - (25% of islet mass) produce hormone GLUCAGON
3. D (delta) cells - (1% of islet mass) synthesize SOMATOSTATIN
4. F cells - produce pancreatic polypeptide (not very well understood)