Basic Info

Question 1

thyroid gland

Answer 1

2nd most common endocrine organ to have pathology

Question 2

where is the thyroid gland located?

Answer 2

in the neck

Question 3

what does the thyroid gland release?

Answer 3

• thyroid hormone (TH) made from thyroglobulin and contain iodine
• calcitonin

Question 4

T3 and T4

Answer 4

triiodothyronine and thyroxinr; T4 is converted to T3 (biologically active form of TH)

Question 5

what does the TH target?

Answer 5

most cells in body to increase metabolic rate

-increase protein/fat/CHO metabolism, heat production, HR –> tachycardia

Question 6

too much TH leads to

Answer 6

hyperthyroidism and grave’s disease

Question 7

too little TH could be due to

Answer 7

dietary iodine deficiency, congenital

Question 8

what cells secrete TH?

Answer 8

follicle cells

Question 9

what is the role of calcitonin?

Answer 9

targets bones and kidneys to decrease Ca levels in the blood (by inhibiting osteoclast activity and increasing excretion Ca in the urine)

Question 10

what cells secrete calcitonin?

Answer 10

C cells aka parafollicular cells

Question 11

what is a goiter?

Answer 11

enlarged thyroid gland

Question 12

what causes a goiter?

Answer 12

hyperthyroidism and hypothyroidism

Question 13

what function does an endemic goiter have?

Answer 13

hypofx

Question 14

why do endemic goiters have hypofx?

Answer 14

d/t deficiency of iodine

Question 15

what is converted to what which is needed for TH synthesis?

Answer 15

iodide is converted to iodine

Question 16

what happens with deficiency of iodine?

Answer 16

TH is made, but has a decreased fx, which stimulates the ant pit to release TSH

Question 17

what does the release of TSH from the ant pit cause in a deficiency of iodine?

Answer 17

causes hyperplasia and hypertrophy of the thyroid gland

Question 18

what is the function like with a toxic goiter?

Answer 18

hyperfx

Question 19

what happens with production of TH in a toxic goiter?

Answer 19

there is excess prod of TH, that do not rely on stimulation from TSH

Question 20

what does the gland look like with a toxic goiter?

Answer 20

gland appears nodular (bumps felt on palpation, seen on imaging)

Question 21

what is the cause of hyperthyroidism?

Answer 21

autoimmunity

Question 22

Grave’s disease

Answer 22

85% of all hyperthyroidism

Question 23

what gender has a higher prevalence of grave’s disease?

Answer 23

women; onset at age 20-40

Question 24

what are the hallmarks of grave’s disease?

Answer 24

• hyperthyroidism
• goiter
• exophthalmos = protruding eyeballs (d/t fluid accumulation in fat pads and orbitus muscle in eye OR excessive retraction of eyelids)

Question 25

what does the hypothalamus synthesize?

Answer 25

oxytocin and ADH and send those to the posterior pituitary

Question 26

what other hormones does the hypothalamus send and where to?

Answer 26

inhibiting or releasing hormones to the pituitary gland to either suppress or stimulate the release of hormones

Question 27

the inhibiting and releasing hormones depend on what to be released?

Answer 27

the demand for hormones, which is communicated via negative feedback

Question 28

what does the posterior pituitary release?

Answer 28

ADH and oxytocin

Question 29

what does the anterior pituitary synthesize and release?

Answer 29

own hormones such as TSH and ACTH (adrenocorticotropic hormone)

Question 30

what do TSH and ACTH stimulate?

Answer 30

respective target organs to prod hormones which then signals back to pituitary and hypothalamus to stop releasing TSH and ACTH in negative feedback loop