endocrine system (Endocrine Glands (Adrenal cortex: secrets…
growth hormone: stimulates growth of all cell and stimulates growth at the epiphyseal plates. secreted all throughout life to maintain cells.
thyroid stimulating hormone: stimulates thyroid to produce hormones.
adrenocorticocotropic hormone: location- cortex of the adrenal glands, stimulate hormone release from cortex
gonadotropins: stimulates testis and ovaries to produce follicle stimulating hormone and luteinizing hormone
prolactin: stimulates the synthesis of milk in breast tissue
thyroid hormone: increases metabolic rate, conversion of nutrients to energy.
calcitonin: secreted from thyroid, only secreted in children, decreases the activity of osteoclasts
patathyroid hormone: they are not directed by anything, detect the amount of calcium in the blood all on their own, and will adjust if the levels fall too low.
targets: kidneys and GI tract.
Adrenal cortex: secrets corticosteroids
Zona Glomerulosa: secretes mineralcorticoids- make kidneys reabsorb/ keep water and sodium
Zona Fasciculata: secretes glucocorticoids- helps keep blood-glucose levels normal, helps deal with long and short term stress. Glucose is brains only source of nutrients and energy
Zona reticularis: secretes glucocorticoids and androgen- in other tissues it becomes testosterone or estrogen
adrenal medulla: secrets epinephrine and nor epinephrine
alpha cells: secrete glucagon to increase blood-glucose
beta cells: secrete insulin to lower blood glucose levels. extra glucose goes to the brain mostly, but also to the liver, skeletal muscle
testes: secrete testosterone
ovaries: secrete estrogen and progesterone
thymus gland: secretes thymic hormones, the gland is big when you're young, but shrinks as you get older and build up your immunity
thymic hormones: cause T-lymphocytes to become immunocompetent. able to produce and immune response to invading pathogens
coordinate, control, and regulate body functions
hormone: chemical messenger in the blood stream
endocrine glands: specialized organ. Ex.) anterior pituitary gland, pineal gland, thyroid, and parathyroid
endocrine tissue (collection of endocrine cells) and endocrine cells: found in the GI: tract, placenta, kidneys, skin, pancreas, thymus, gonads, hypothalamus, heart
target cell: a cell that specific hormones attach to after they are released from a group of endocrine cells. The target cells have receptors that are compatible with certain hormones.
exocrine glands: products of exocrine glands remain on the apical surface of hollow organs (not in the blood stream). They contain ducts.
Endocrine glands do not contain ducts, secretions end up in the blood stream and flow throughout the body.
nervous system vs Endocrine system
nervous system: neurotransmitters
endocrine system: hormones
site of messenger action
nervous system: axon terminal> synapse> binds with target cell (generally located close together)
endocrine system: target cell, no matter how far or close they are located
types of target cells
nervous system: skeletal muscle, cardiac muscle, smooth muscle, and glands
endocrine system: various cells throughout the body ( target cells)
duration of action
nervous system: milliseconds, the signal needs to be continuous in order to last longer
endocrine system: hours or days
time to onset of action
nervous system: milliseconds, very short
endocrine: depends on the action, not as fast. seconds or hours or days
Hypothalamus and pituitary gland
hypothalamus affect on the anterior pituitary gland : secretes hormones that stimulate the release of hormones from the anterior pituitary gland. Or secretes hormones that inhibits hormone release from anterior pituitary gland
hypothalamus affect on posterior pituitary gland: synthesizes 2 hormones that are stored in axon terminals in posterior pituitary gland.
anterior pituitary: true endocrine gland: produces and secretes hormones
posterior pituitary gland: not a true endocrine gland, part of the brain, does not manufacture hormones, just stores hormones.