Chapter 6 Study Questions (Part 3) Flashcards
how is oxytocin release regulated?
positive feedback
why is the regulation of oxytocin relevant?
it’s positive feedback, and the rest of the hormones use negative feedback
what are the two main functions of oxytocin?
- released during labor
- sckling response for newborn
what is a tropic hormone?
a hormone that comes from the source cell and causes a target cell to make a hormone
what makes TH active?
the addition of iodine
what are the three versions of iodine?
T3, T4, reverse T3
T3
active form of TH
T4
much less active, storage form of TH
reverse T3
occurs with prolonged illness, inactive form of TH
active form of TH
T3
much less active storage form of TH
T4
occurs with prolonged illness, inactive form of TH
reverse T3
what are the steps of thyroid hormone synthesis? (6/7)
- thyroglobulin is exocytosed
2+3. exocytosed and oxidized - conjugation
- endocytosed
- proteolysis
- exported
the TH transporter effectively provides a way to store a hydrophobic hormone and control its dosage release to the body. why?
bound to carrier protein.
what is the job of the TH transporter protein?
- store a hydrophobic hormone
- control dosage release into the body
where is the TH receptor located. why?
inside. TH is hydrophobic, so it gets through the membrane with no problem.
what does the location of the TH receptor tell you about how TH acts on a cell?
inside: slow-acting –> DNA translation/transcription, lasts longer
how does thyroid hormone increase body temperature?
breaks down glucose/fatty acids to make ATP, and some energy is always lost as heat
what effect does TH have on UCP? and what is even UCP?
UCP = uncoupling protein
TH turns on gene expression for UCP which converts kinetic to chemical energy
how is T4 different from T3?
T4 has an additional iodine atom and is considerable less active
you suspect your patient has hypothyroidism. what do you do? (3)
- check thyroid hormone levels
- check thyroid releasing hormone levels
- check thyroid stimulating hormone levels
what is the role of melatonin?
sleep aid
what is the role of calcitonin?
tones down calcium
what is the role of parathyroid hormone?
increase calcium absorption from diet, release calcium from bones
