Lecture 8 Flashcards
1
Q
3 Main types of Hormones
A
- Peptide/Protein
- Steroid
- Amine
2
Q
2 classifications of hormones
A
- Hydrophilic
- Hydrophobic
3
Q
Hydrophilic Hormones
A
- Water soluble, plasma soluble
- Lipid insoluble (lipophobic)
- Unable to cross through plasma membranes
4
Q
Hydrophobic hormones
A
- Water insoluble, plasma insoluble
- Lipid soluble (lipophilic)
- Rapidly crosses the plasma membrane
5
Q
What are peptide/protein hormones derived from?
A
3 or more amino acids
6
Q
What are steroid hormones derived from?
A
cholesterol
7
Q
What are amine hormones derived from?
A
single amino acids
8
Q
Melatonin
A
- Secreted at night (sleep)
- Made in the pineal gland (also gi tract, leukocytes and other brain regions)
9
Q
Amine Hormones
A
Synthesized only from tryptophan or tyrosine
10
Q
Tryptophan derivative
A
melatonin (behaves like peptides or steroids)
11
Q
Tyrosine derivatives
A
- catecholamines (behave like peptides)
- Thyroid hormones (behave like steroids)
12
Q
Control of hormone release
A
endocrine cells directly sense stimuli, then secrete the hormone
13
Q
Synergistic Effects
A
- Multiple hormones act together for greater effect
- Synergism between FSH and testosterone on sperm production
14
Q
Permissive Effects
A
- One hormone enhances the target organ’s response to a second later hormone
- Estrogen prepares the uterus for action of progesterone
15
Q
Antagonistic Effects
A
- One hormone opposes the action of another
- Insulin lowers blood glucose and glucagon raises it
