thyroid

Question 1

site of production of thyroid hormone?

Answer 1

follicles

Question 2

where are the 4 parathyroid glands?

Answer 2

posterior part of gland

Question 3

what cells produce there hormone and encircle the colloid in which the hormone passes into for storage line them ?

Answer 3

cuboidal epithelial cells

Question 4

what are parafollicular cells?

Answer 4

found outside the follicles

Question 5

what do parafollicular cells produce

Answer 5

calcitonin

Question 6

production and releease of thyroid hormones is under the control of

Answer 6

hypothalamic pituitary axis

Question 7

where is TRH released from ?

Answer 7

hypothalamus

Question 8

TSH?

Answer 8

pituitary

Question 9

what feedback does thyroid hormone exhibit on both TRH and TSH?

Answer 9

negative feedback

Question 10

what does stress do to TRH?TSH?

Answer 10

decrese

Question 11

what does cold do to TRH in children>

Answer 11

stimulates TRH release (to warm up)

Question 12

when is release of TRH highest?

Answer 12

in the evening

Question 13

90% of thyroid hormone produced is?

Answer 13

T4

Question 14

10% of thyroid hormone produced is?

Answer 14

T3

Question 15

which one is thyroxine?

Answer 15

T4

Question 16

thyroid hormone is produced via uptake of _______ which is attached to _______ __________ of _________ to produce either T3 or T4?

Answer 16

iodine

tyrosine residues of thyroglobulin

Question 17

upon release, what three binding globulins does T3 and T4 bind to?

Answer 17

thyroxine binding globulin
thyroxin binding pre albumin
albumin

Question 18

what is the main binding globulin?

Answer 18

thyroid binding globulin

Question 19

when are levels of TBG increased?

Answer 19

pregnancy
COCP
tamoxifen
hepatitis

Question 20

decreased levels of TBG?

Answer 20

cushings
large dose of steroid
nephrotic syndrome

Question 21

is bound t3/t4 active

Answer 21

no, only free

Question 22

what is the most biologically active form of thyroid hormone?

Answer 22

T3

Question 23

where does T4 undergo peripheral conversion to T3?

Answer 23

in the skin, kidneys and liver upon release into circulation

Question 24

biological effects of T3?

Answer 24

increased thermogenesis
increased basal metabolic rate
increased carbohydrate and lipid breakdown, protein synthesis
causes growth
normal cognitive function
enhancement of response to sympathetic nervous system due to increased expression of receptors