E2

Question 1

Parathyroid gland

6

Answer 1

Small endocrine glands
Yellowish-brown flat ovoid shape
Posterior aspect of thyroid
4 usually 
Cells densely packed 
Produce parathyroid hormone

Question 2

Parathyroid gland cells

2

Answer 2

Chief cells

Oxyphil cells

Question 3

Chief cells

Answer 3

Synthesize and secrete PTH

Question 4

Oxyphil cells

Answer 4

Function unknown

Question 5

PTH

3

Answer 5

Amino acid based hormone
Binds to target cell G-protein coupled receptors
CAMP and phospholipase second messenger systems

Question 6

Fxns of PTH

2

Answer 6

Antagonist to calcitonin hormone from thyroid

increases blood Ca2 levels

Question 7

How does PTH increase levels of calcium in the blood

3

Answer 7

In bone it stimulates osteoclasts (which breaks down bone matrix)
In kidney it resorbs calcium and excretes PO43-
In intestine calcium is absorbed via mucosal cells

Question 8

Calcium derived from ingested food in the intestine requires what to be absorbed

Answer 8

Calcitriol which is the active form of vitamin D3

Question 9

Intestinal absorption of calcium pathway:

3 steps

Answer 9

Vitamin D (inactive form) from either diet or sun –> kidneys: vit D (inactive form) converted to Calcitriol (active form), stimulated by PTH. –> calcium absorption by intestinal mucosal cells

Question 10

Parathyroid hormone disorders

Answer 10

Hypocalcemia
Hypercalcemia
Hypoparathroidism
Hyperparqthyroidism

Question 11

Hypocalcemia

Answer 11

Decrease blood calcium, results in excitability of nervous system, i.e. Tentany, muscle twitches, and convulsions

Question 12

Hypercalcemia

Answer 12

Increase blood calcium, results in depression of nervous system, kidney stones and soft tissue calcification

Question 13

Hypoparathyroidism

Answer 13

Decreased PTH. Trauma or gland removal; decreased calcium, i.e. Tetany

Question 14

Hyperparathyroidism

Answer 14

Increased PTH. tumor’ increased blood calcium, decreased bone density, i.e. Metastatic calcification, osteitis fibrosis cystic

Question 15

Adrenal glands (4)

Answer 15

• AKA Suprarenal Glands
• Pyramid-shaped, on top of kidneys
• Adrenal Cortex- outer portion
• Adrenal Medulla- inner portion

Question 16

Layers of Adrenal Cortex

3

Answer 16

Zona glomerulosa
Zona fasciculate
Zona reticularis

Question 17

Zona glomerulosa

Answer 17

outer layer, produces mineralocorticoids, i.e. aldosterone

Question 18

Zona fasciculate

Answer 18

middle layer, produces glucocorticoids, i.e. cortisol

Question 19

Zona reticularis

Answer 19

inner layer- produces gonadocorticoids, i.e. estrogens, progestogens, & weak androgens

Question 20

Mineralocorticoids

4

Answer 20

• Regulate concentrations of Na⁺ & K⁺
• Aldosterone most potent
• Stimulates Na⁺ reabsorption from kidney tubule to blood
• Stimulus for secretion: ↓ Na⁺, or ↑ K⁺ in blood and ↓ blood volume & pressure

Question 21

Renin-angiotensin aldosterone system

Answer 21

RAAS

↓ BP or BV → juxtaglomerular apparatus cells of kidney release renin → converts angiotensinogen (plasma protein produced in liver) to angiotensin I → In lung capillaries primarily but not exclusively, ACE (angiotensin-converting enzyme converts angiotensin I into angiotensin II (causes vasoconstriction & ↑BP) → Release of aldosterone (zona glomerulosa- outer layer) cells of adrenal cortex → Na⁺ reabsorption from kidney tubules into blood. H₂O moves with Na⁺ and therefore increases blood volume & pressure.

Question 22

Regulation of Aldosterone Secretion

4

Answer 22

RAAS
Plasma concentration of K⁺ & Na⁺
ACTH
ANP

Question 23

Plasma concentration of K⁺ & Na⁺

Answer 23

• ↑ K or ↓ Na directly causes ↑ aldosterone secretion by zona glomerulosa.

Question 24

ACTH

Answer 24

↑ ACTH w/ stress causes ↑ aldosterone secretion by zona glomerulosa.

Question 25

ANP

Answer 25

atrial natriuretic peptide. ↑ BP causes secretion of ANP by heart. ANP blocks renin & aldosterone secretion and inhibits renin-angiotensin mechanism, therefore ↓ BP.

Question 26

Glucocorticoids 4

Answer 26

* Normally maintain blood glucose & BP * Cortisol is primary glucocorticoid in humans * Provokes gluconeogenesis during severe stress * Enhances epinephrine vasoconstrictive effects

Question 27

Gonadocorticoids | 2

Answer 27

Weak androgens & small amounts of estrogens | Provide estrogens after menopause

Question 28

Epinephrine | 3

Answer 28

* Stimulate metabolic activities * Bronchodilation * Increase blood flow to skeletal muscles & heart

Question 29

Norepinephrine | 2

Answer 29

* Peripheral vasoconstriction | * Therefore, increased blood pressure

Question 30

Addison’s

Answer 30

↓ glucocorticoids & mineralocorticoids. ↓ blood glucose & Na⁺. Weight loss.

Question 31

Cushings

Answer 31

↑ glucocorticoids; steroid diabetes, edema & hypertension. Moon face (swelling), and buffalo hump (fat redistribution)

Question 32

Exocrine Function of Pancreas | 4

Answer 32

* Acinar cells surround ducts * Produce pancreatic juice * Pancreatic juice contains digestive enzymes * Breaks down carbohydrates (pancreatic amylase), fats (lipase), proteins (proteases: trypsin & chymotrypsin), and nucleic acids (nucleases)

Question 33

Endocrine Function of Pancreas | 4

Answer 33

* Islets of Langerhan cells * Alpha cells produce Glucagon * Beta cells produce Insulin & Amylin * Delta cells secrete Somatostatin

Question 34

Insulin | 4

Answer 34

Secreted by beta cells of Islets of Langerhans Amino acid based hormone 2 polypeptide chains linked by disulfide bonds Derived from “clipping” of proinsulin molecule

Question 35

Functions of Insulin

Answer 35

1. ) Lowers blood glucose level 2. ) Stimulates membrane transport of glucose (muscle & fat cells, not brain, liver, or kidney) into target cell 3. ) Stimulates amino acid uptake into target cell

Question 36

Intracellular Effects of Insulin

Answer 36

* Stimulates formation of glycogen from glucose in liver & muscle * Inhibits glycogenolysis (break down of glycogen to glucose) in liver & muscle * Stimulates protein synthesis from amino acids in muscle * Inhibits protein catabolism (breakdown of protein) in muscle * Stimulates fatty acid synthesis in liver * Inhibit lipolysis (breakdown of fats) in adipose tissue * Inhibits gluconeogenesis (conversion of amino acids & fats to glucose) in liver

Question 37

Tunica vaginalis of testes

Answer 37

outer serous membrane