Quiz 2 Flashcards
Hormones are signal molecules for ____-distance communication secreted into the ______ by _______ cells.
Long; Blood; Endocrine
What are the 3 classes of hormones?
- Peptide
- Steroid
- Amine
What are the characteristics of peptide hormones?
-initial protein in the rough ER
-storage in secretory vesicle
-released by exocytosis
-Lipophobic/ hydrophillic
-Short half-life
What are the characteristics of steroid hormones?
-Lipophillic/ Hydrophobic
-Synthesized on demand
-Released by simple diffusion
-Bind to protein carriers in the blood
-Longer half-life
What are the kinds of Amine hormones?
- Tryptophan - derived (lipophillic)
- Tyrosine-derived:
- Catecholamines (lipophobic)
- Thyroid Hormones (lipophillic)
What is the simple endocrine pathway? What are some examples?
Endocrine cell directly senses stimulus, integrates, and responds by secreting hormone. Ex: pancreas
What is the complex insulin endocrine pathway?
Pancreatic endocrine cells evaluate 3 input signals when “deciding” whether and how much insulin to secrete.
What does the posterior pituitary secrete? What do they do?
Vasopressin: water balance in kidneys
Oxytocin: uterine contractions
What are the 6 tropic hormones released by the anterior pituitary? What do they do?
1&2. LH & FSH: reproduction & metabolism
3. Prolactin: milk production
4. Thyroid stimulating hormone (TSH): development & metabolism
5. Growth hormone (GH): growth & metabolism
6. Adrenocorticotropic hormone (ACTH): stress & metabolism
What is long-loop feedback?
Peripheral gland secretion inhibits secretion by hypothalamus & anterior pituitary
What is short-loop feedback?
Anterior pituitary secretion inhibits secretion by hypothalamus
What is synergism?
Combined effect of hormones is greater than additive
What is permissiveness?
Hormone has no effect by itself, but is necessary for other hormone’s full effect
What is antagonism?
Two hormones have opposing effects
What is hypersecretion?
Hormone excess
