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Flashcards in thyroid histology Deck (27)
1

what is the first endocrine gland to develop?

thyroid gland

2

what is the thyroid gland derived from?

is derived from endoderm in the floor of the primitive pharynx

3

when does the thyroid begin to fxn?

by the end of the 3rd month prenatally

4

what is the thyroid capsule derived from?

deep cervical fascia

5

what partitiions the gland into lobules?

trabeculae/septa

6

which hormones does the thyroid gland synethesize?

T3, T4, Calcitonin

7

if cells in follicular epithelium are simple squamous, what level of activity?

low

8

if cells in follicular epithelium are simple cuboidal, what level of activity?

normal

9

if cells in follicular epithelium are simple columnar, what level of activity?

high

10

thyroid follicles are surrounded by_____

basal lamina

11

what is in the follicular lumen?

colloid

12

what is in colloid?

thyrogloblin (T3 + T4)

13

where is calcitonin stored and released from?

parafollicular cells in the thyroid gland

14

synthesis of thyroid hormones is controlled by ____ and ____

TSH and iodide

15

thyroglobulin synthesis occurs in the ______, thyroglobulin glycosylation occurs in the _____&______

RER; RER & GA

16

how many tyrosine residues are found in each thyroglobulin molec?

120

17

what sort of transport is required for iodide to enter follicular cells?

active transport

18

the transepithelial pathway involves binding of thyroglobulin to ______

megalin

19

where is megalin located?

apical follicular cell membrane, facing the colloid

20

during the lysosome pathway or the transepithelial pathway does the T3 T4 get released when attached to thryoglobulin?

transpithelial

21

which pharyngeal pouches do the parathyroid glands arise from?

3rd, 4th

22

how are epithelial cells arranged in parathyroid gland parenchyma?

cords or clusters

23

which cells synthesize parathyroid hormone?

chief cells

24

in bone, PTH attaches to _____ receptors, but triggers ______activity

osteoblast receptors, osteoclast activity

25

osteoclast = bone building or bone breakdown?

bone breakdown

26

in kidney, PTH ____Ca loss in urine, ______phosphate loss in urine

prevents Ca loss, promotes phosphate loss

27

tetany can result from loss of what?

parathyroid (loss of Ca)