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Flashcards in Thyroid Deck (54)
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1

what is the main raw material of thyroid hormone

how do we get this raw material

what happens next

inorganic iodide

provided by the diet

extracted from the blood and converted to organic iodine

2

iodide ingested and taken into the blood is converted to
--> ___ + ___
--> ____ + ____
--> ____

iodine which binds to tyrosine

which forms monoiodtyrosine which binds with iodine

which forms diiodotyrosine

3

what forms T4

diiodotyrosine + diiodotyrosine = tetra/thyroxin

4

what is another name for T4

thyroxin
tetraiodothyronine

5

what forms T3

monoiodotyrosine + diiodotyrosine

6

what is another name for T3

triiodothyronine

7

what is thyroid hormone stored in? as what ?

acini

thyroglobulin

8

most of thyroid hormone in circulation is what type

T4 90%

9

99% of T4 and T3 are bound to what in the blood

protein

10

most of T4 is bound to what

most of T3 is bound to what

TBG (thyroid binding globulin)

TBG and albumin

11

thyroid binding globulin is what type of protein

alpha 1 globulin

12

1% of T4 and T3 is found where

FREE or unbounded

metabolically active in cells

13

free T4 is converted to

where

T3

in the liver cells for utilization

14

what percent of daily T3 is converted and utilized by the liver

80%

15

80% of __ is converted and utilized by the liver

T3

16

decreased levels of T3 and T4 cause what to happen

TRH production in hypothalamus

17

increased levels of T3 and T4 cause what to happen

inhibit TSH and TRH

18

TSH high, T3 and T4 are low indicate what

primary hypothyroidism

(hashimotos)

19

TSH is normal or low
T3 and T4 are low
indicates what

secondary hypothyroidism

20

why is TSH normal or low in secondary hypothyroidism

pituitary doest respond to TRH or low T3/T4 doesnt trigger TRH response

21

TSH is low and
T3 and T4 are high indicates what

hyperthyroidism

22

is T3 or T4 more elevated in hyperthyroidism

T3

23

what causes hyperthyroidism

due to autonomous hyperfunction or thyroid stimulators in the blood

24

what is graves disease

hyperthyroidism

25

what is another name for graves disease

diffuse toxic goiter

26

what are the requirements to have graves disease

hyperthyroidism and one of the following:
goiter
exophthalmous
pretibial myxedema

27

what causes graves disease

due to circulating antobodies against TSH receptors which causes continuous secretion of T3/T4

28

what is the most common cause of hyperthyroidism

graves disease

29

what results from the ingestion of thyroid hormone

thyrotoxicosis factitia

30

calcitonin is made by what cells of the thyroid gland

C cells of thyroid