Lecture 6

Question 1

Describe synthesis, storage, release, transport, half-life, receptor locations, and general response for peptide hormones

Answer 1

Most common class
synthesized by endocrine cells throughout body
stored in intracellular vesicles (lipophobic)
released through exocytosis
transported through diffusion in plasma
short half-life
receptors on membrane
modification of protein activity

Question 2

Describe synthesis, storage, release, transport, half-life, receptor locations, and general response for steroid hormones

Answer 2

synthesized by adrenal cortex, skin, kidneys, gonads, placenta
produced on demand from lipid precursors (these can be stored)
released by diffusion
transported by carrier molecule
long half-life
receptors in cytoplasm/nucleus
results in protein synthesis

Question 3

Describe synthesis, storage, release, transport, half-life, receptor locations, and general response for amine hormones

Answer 3

Synthesized by adrenal medulla, pineal gland, thyroid gland
Catecholamines are similar to peptide hormones.synthesized by endocrine cells throughout body
stored in intracellular vesicles (lipophobic)
released through exocytosis
transported through diffusion in plasma
short half-life
receptors on membrane
modification of protein activity

Thyroid hormones are similar to steroid hormones
Difference: only nucleus receptors
produced on demand from lipid precursors (these can be stored)
released by diffusion
transported by carrier molecule
long half-life
receptors in nucleus
results in protein synthesis

Question 4

What is the difference between the ant and post pit

Answer 4

post pit receives and stores vesicles containing neurohormones from hypothalamus and releases into the blood
ant pituitary is a true endocrine gland

Question 5

Give an example of a simple endocrine reflex

Answer 5

low calcium sensed by parathyroid cell, releases parathyroid hormone. Results in breakdown of bone, increased Ca uptake by kidney, increased absorption of Ca in the intestines