endocrine system Flashcards
predator and prey endocrine system connection
flight or flight response governed by hormones
endocrine system
internal secretion
*hormones
paracrine system
regional signaling; ex. between organs in GI tract
autocrine system
self secretion signaling between cells; ex immune system
exocrine system
external secretion; pheromones
2 types of hormones
hydrophobic and hydrophilic
hydrophilic hormones
require cell surface receptor
*peptide hormones (oxytocin, ADH)
*amine hormones (derived from amino acids)
hydrophobic hormones
hormone receptor complex in cytoplasm bc can cross lipid bilayer easily
*steroid hormones (progesterone, testosterone, cortisol, cholesterol)
- corticosteroids and sex steroids
differences between hydrophobic and hydrophilic hormones
- abundance (hydrophilic more abundant)
- how they enter cell
-signaling time
-effect lasting time
which type of hormone last longer
hydrophobic
*therefore broader impact
which type of hormone response is quicker
hydrophillic
hypothalamus role in endocrine system
releasing factors to pituitary gland
pituitary gland targets
thyroid, adrenal glands (only in endocrine system)
lungs, kidneys, digestive tract
posterior pituitary gland
hormones made in hypothalamus, stored in posterior, neurons in hypothalamus signal release
anterior pituitary gland
neurons in the hypothalamus signal releasing factor to create and release more hormones
pituitary targets that ONLY function as part of endocrine system
thyroid, adrenal glands
pituitary targets that have endocrine AND other functions
lungs, kidneys, digestive tract
hypothalmus function
transmit signals (release factors) to pituitary gland; neurosecretory cells -> releasing hormones
tropic hormones
hormones that control the release of other hormones:
FSH, LH, ACTH, thyroid stimulating hormone
FSH and LH
ovaries release estrogen and testes produce testosterone
ACTH
adrenal glands release cortisol
direct hormones and functions
- prolactin: stimulate lactation
- endorphins
- growth hormone
posterior pituitary gland hormones (stores)
oxytocin and ADH/ vasopressin
oxytocin function
- female reproductive
- contractions during birth
Vasopressin function
- kidneys (conc of urine)
- maintain water and solute balance
how are stored hormones released from posterior pituitary gland
stores in axons from the hypothalamus -> release hormones into capillary beds to body
high blood sugar negative feedback
high blood glucose -> beta cells in pancreas secrete insulin (hormone) -> glucose stored as glycogen
low blood sugar negative feedback
alpha cells from pancreas secrete hormone glucagon -> glycogen to glucose for energy
what hormone released when blood sugar is high
insulin
what hormone released when blood sugar is low
glucagon
how is stress amplified by the ES
Hypothalamus 1 mg corticotropin releasing factor -> anterior pituitary gland (1 mg hormone) -> adrenal cortex (40 mg cortisol) -> liver (5600 mg glycogen)
* gives body energy for survival
what kind of feedback is amplification
positive feedback
positive feedback: birth
head pushes against cervix -> hypothalamus -> pituitary gland release oxytocin -> oxytocin stimulates contractions -> cycle
pheromone functions in animals (3)
- signal readiness for reproduction (ex. ladybugs)
- marking territory (ex. dogs and wolves)
- alert colony of food (ex. ants)
trail pheromones
alert other soil insects of food nearby
