Chapter 6 Study Questions (Part 3)

Question 1

how is oxytocin release regulated?

Answer 1

positive feedback

Question 2

why is the regulation of oxytocin relevant?

Answer 2

it’s positive feedback, and the rest of the hormones use negative feedback

Question 3

what are the two main functions of oxytocin?

Answer 3

1. released during labor
2. sckling response for newborn

Question 4

what is a tropic hormone?

Answer 4

a hormone that comes from the source cell and causes a target cell to make a hormone

Question 5

what makes TH active?

Answer 5

the addition of iodine

Question 6

what are the three versions of iodine?

Answer 6

T3, T4, reverse T3

Question 7

T3

Answer 7

active form of TH

Question 8

T4

Answer 8

much less active, storage form of TH

Question 9

reverse T3

Answer 9

occurs with prolonged illness, inactive form of TH

Question 10

active form of TH

Answer 10

T3

Question 11

much less active storage form of TH

Answer 11

T4

Question 12

occurs with prolonged illness, inactive form of TH

Answer 12

reverse T3

Question 13

what are the steps of thyroid hormone synthesis? (6/7)

Answer 13

1. thyroglobulin is exocytosed
   2+3. exocytosed and oxidized
2. conjugation
3. endocytosed
4. proteolysis
5. exported

Question 14

the TH transporter effectively provides a way to store a hydrophobic hormone and control its dosage release to the body. why?

Answer 14

bound to carrier protein.

Question 15

what is the job of the TH transporter protein?

Answer 15

1. store a hydrophobic hormone
2. control dosage release into the body

Question 16

where is the TH receptor located. why?

Answer 16

inside. TH is hydrophobic, so it gets through the membrane with no problem.

Question 17

what does the location of the TH receptor tell you about how TH acts on a cell?

Answer 17

inside: slow-acting –> DNA translation/transcription, lasts longer

Question 18

how does thyroid hormone increase body temperature?

Answer 18

breaks down glucose/fatty acids to make ATP, and some energy is always lost as heat

Question 19

what effect does TH have on UCP? and what is even UCP?

Answer 19

UCP = uncoupling protein

TH turns on gene expression for UCP which converts kinetic to chemical energy

Question 20

how is T4 different from T3?

Answer 20

T4 has an additional iodine atom and is considerable less active

Question 21

you suspect your patient has hypothyroidism. what do you do? (3)

Answer 21

1. check thyroid hormone levels
2. check thyroid releasing hormone levels
3. check thyroid stimulating hormone levels

Question 22

what is the role of melatonin?

Answer 22

sleep aid

Question 23

what is the role of calcitonin?

Answer 23

tones down calcium

Question 24

what is the role of parathyroid hormone?

Answer 24

increase calcium absorption from diet, release calcium from bones