Endocrine System Flashcards
Difference between neurotransmitter and a hormone
Neurotransmitter: released into synaptic cleft + chemical messenger, released by the nervous system
Hormone: released directly into blood streatm, need blood capillaries to pick up, released by the endocrine system
Examples of neurotransmitters
acetylcholine, norepinephrine, dopamine, glycine, GABA, serotonin
Examples of hormones
epinephrine, oxytocin, ADH, melatonin, cortisol
Examples of both neurotransmitters and hormones
epinephrine, norepinephrine, nitric oxide
Exclusive endocrine glands
Pituitary, thyroid, parathyroid, pineal, adrenal
Not exclusive endocrine glands
pancreas, ovaries, testes, thymus, hypothalamus, kidney, stomach, liver
What roles do hormones play within our body
Synthesis of new molecules (protein anabolism)
Changing permeability of the cell membrane
Stimulating transport of a substance into or out of the cell
Altering the rate of metabolic actions
Causing contraction of smooth or cardiac muscle
Water soluble hormones
have receptors on the plasma membrane and uses second messenger to regulate cellular processes
Lipid soluble hormones
do not have receptors on the plasma membrane instead have receptors either in the cytosol or the nucleus and directly affect the gene expression
Synergistic
when two or more hormones combine to produce effects
Permissive
presence of one hormone is required for another hormone to exert its full effects on a target cell (T3 and T4 or thyroid hormones and epinephrine; cortisol and growth hormone)
Agonist
a substance which initiates a physiological response when combined with a receptor (all hormones)
Antagonist
the act to return body conditions to within acceptable limits from opposite extremes care called antagonistic hormone (insulin and glucagon; parathyroid hormones and calcitonin; aldosterone and atrial natriuretic peptide (ANP))
Hypothalamic releasing and inhibiting hormones
GNRH; GHIH, GnRH, TRH; CRH; PRH, PIH (dopamine)
Other hypothalamic hormones
ADH and oxytocin
