Thyroid gland Flashcards Preview

Endocrinology > Thyroid gland > Flashcards

Flashcards in Thyroid gland Deck (30):
1

what temporarily connects the developing thyroid gland to the foramen cecum of tongue?

thyroglossal duct

2

what cares blood vessels, lymphatic vessels, and nerve fibers deep into glands?

septa

3

What covers the posterior surface of thyroid gland

parathyroid gland

4

What does T3 and T4 regulate

cell and tissue metabolism, head production

5

what does calcitonin regulate

blood calcium levels

6

how does the follicular epithelium change in response to activity?

low: simple squamous
normal:simple cuboidal
High active:simple columnar

7

what secretes calcitonin

parafollicular cells ( C cells)

8

when is calcitonin released?

released when blood calcium are high. It LOWERS blood calcium level to normal

9

How does calcitonin regulate calcium levels

-inhibit bone breakdown by osteoclasts
-Promote calcium deposition in bones (osteoid calcification)
-increase Ca excretion

10

What hormone travels down to thyroid gland to initatiate T3 and T4 production

TSH

11

Where are vesicles formed in the follicluar cell?

Golgi apparatus

12

What does each thyroglobulin molecule contain when it exocytose?

120-140 tyrosine residues

13

How does the iodide get into the thyroid gland

enters folliclular cell via active transport via Na/iodide symportersat the basal membrane of follicular cells

14

when Triiodinated tyrosine and tetraiodinated tyrosine gets cleaved from thyroglobulin, what does it become?

T3 and T4

15

How is T4 produced?

thyroid follicular cell

16

How is T3 produced?

Conversion of T4 by kidney, liver

17

what are some signs of hyperthyroidism? and what disease does it cause?

Graves disease: exophthalamos, enlarged thryoid

18

what cells synthesize and release parathyroid hormone?

chief cells

19

what is the function of Parathryoid hormone (PTH)

regulates calcium and phosphate levels in the blood

20

PTH in bone effect

PTH attaches to osteoblast receptors-->cause osteoblast to release OsteoCLAST-stimulating factor-->osteoclast activity breaking down bone-->freeing calcium from bone to enter blood stream

21

PTH in Kidney effect

PTH: conserves Ca and excretes phoshpate.

initiate calcitriol synthesis.

reasborption of Ca from filtrate

22

PTH in GI

regulate formation of vit D in kidneys, PTH controls rate of calcium (via VItamin D, because VItamin D facilitates Ca absorption in GI)

23

which hormone decreases elevated blood Ca++ levels to normal?

Calcitonin

24

what happens when you completely remove parathyroid gland?

drop in blood calcium level causing Hypoparathryoidism-->hypocalcemia-->tetany

25

Hyperparathryoidism effects

cause hypercalcemia-->urinary tract stone (calcification)

26

which cells synthesize glucagon in pancreas

alpha cells

27

which cell synthesize insulin in pancreas?

beta cells

28

what increases blood glucose level? decrease blood glucose level

Glucagon;insulin

29

What do delta cells synthesize? and what is its function?

Somatostatin
reduce smooth muscle contraction of digestive tract and gall bladder

decrease insulin and glucagon

30

What does G cells synthesize? function?

Gastrin; stimulate parietal cells to produce HCl