chapter 45 Flashcards
what are animal hormones?
chemical signals secreted in extracellular fluid, send messages
where do hormones circulate?
throughout body through blood/hemolymph
what is the endocrine system?
chemical signalling by hormones
what is the nervous system?
transmit signals through body through neurons
how are signals transmitted between cell classified?
type: type of cell secretion
route: route taken by the cell when reaching its target
what is endocrine signaling?
secreted molecules diffuse into the bloodstream and trigger responses in target cells anywhere in the body
what are the 4 goals of the endocrine signalling?
- maintain homeostasis
- mediates responses to environmental stimuli
- regulates growth and development
- triggers physical and behavioral changes for sexual maturity and reproduction
what is local regulator?
travels short distances by diffusion
what is paracrine signalling?
the target cells lie near their secreting cell
what is autocrine signalling?
the target cell is the same cell as the signalling cell
what roles do paracrine and autocrine play?
blood pressure, nervous system, reproduction
what are prostaglandins in males?
produce semen
what are prostaglandins in females?
stimulate uterine walls to contract so sperm can find eggs and also induces labor
what are prostaglandins in the immune system?
cause contractions, inflammation, and pain
how does aspirin and ibuprofin work?
block prostaglandins to reduce pain
what is synaptic signalling?
neurons form synapses with target cells (not local)
what are synapses?
junction between 2 or more cells
what are neurotransmitters?
diffuse a very short distance and bind to receptors on the target cells, play a role in memory, movements, and learning
what is the neuroendocrine signaling?
neurosesecretory cells secrete neurohormones
what are neurohormones?
diffuse from nerve cell endings into the bloodstream (ex. antidiuretic hormone which is essential to kidney function and water balance)
what are pheromones?
chemicals released externally (ex, leads ants to food, attract mates)
what are the 3 classes of local regulators?
- modified fatty acid (insulin)
- polypeptides (cytokines and growth factors)
- gases
whats with nitric oxide?
is regulates vasodilation and increases blood flow in men
how does viagra work?
prolongs activity of nitric acid in blood oxide
what is epinephrine?
fight or flight hormone, can have different receptors and therefore different effects
what are endocrine glands?
do not have a duct that sends hormones out so they secrete hormones directly into surrounding fluid (thyroids, gonads)
what are exocrine glands?
have a specific duct that carry secreted substances (salivary glands)
what is the pineal gland?
secretes melatonin that plays a role in regulation of biological rhythms
what is the hypothalamus?
hormones released from posterior pituitary, releases and inhibits hormones regulate anterior pituitary
what is the anterior pituitary gland?
follicle-stimulating hormone and luteinizing hormone-stimulate ovaries and testes
prolactin-stimulates mammary gland cells
growth hormones-stimulates growth and metabloic functions
what is the posterior pituitary gland?
oxytocin- stimulates contracts of uterus
vasopressin (ADH)- water retention of kidneys
what is the thyroid gland?
secretes thyroid hormone- maintains metabolic processes
what is the adrenal medulla?
epinephrine and norepinephrine- raise blood glucose, metabolic activites
what is the adrenal cortex?
glucocorticoids-raise blood glucose level
mineralcorticoids-reabsorb sodium and secretion of potassium in kidneys
what is the pancreas?
insulin-lowers blood glucose
glucagon- raises blood glucose level
what happens when blood calcium is low?
skeletal muscles contract and cause convulsions
what happens when blood calcium is high?
organ damage bc of formation of calcium phosphate
what 2 antagonistic hormones regulate the homeostasis of calcium in mammals?
Parathyroid hormone in parathyroid gland
calcitonin in thyroid inhibits bone breakdown and causes kidneys to excrete more calcium
where are the adrenal glands located?
top of kidneys
adrenal gland is made up of
the adrenal medulla and adrenal cortex
when is epinephrine secreted?
short term life threatening events
what are corticosteroids?
long term steroids, triggered by hormone cascade pathway via hypthalamus and anterior pituitary
what are glucocortoids?
cortisol, antiflammatory, break down fats
what are mineralcorticoids?
ion and water balances, increase blood pressure
where are sex hormones produced?
donads, testes and ovaries
what are sex hormones?
affect growth,development, reproductive cycles and sexual behaviors
what are the 3 types of steroid sex hormones?
androgens, estrogens, and progestins
what is the main androgen?
testosterone
what is the main estrogen?
estradiol
what does testosterone do?
stimulate development of male reproductive tract (low voice, body hair, muscle mass)
what does bipotential gland do?
develops to be either girl/boy
what is the anti-mullerian hormone?
cause female parts to degenerate
what are estrogens?
development of female secondary characteristics?
what do progestins and progesterones do?
prepare uterus to support the growth and development of an embryo
what is an endocrine disrupter?
block function of normal hormone pathway
what does the thyroid hormone do in frogs and humans?
tail absorption and weight, temp regulator, and tiredness
show hormones go through divergent evolution
what does melanocyte-stimulating hormone in amphibians and mammals?
regulating pigmentation and deal with apeitite and pregnancy
