Endocrine System Flashcards
outgoing signal -> physiological response in another cell
cell-cell communication
conversion of an impulse or stimulus from one physical or chemical form to another
signal transduction
signal binds receptor proteins, initiating a
physiological response
general principles of cell signaling
signals can act over a long or short range
a limited set a extracellular signals can produce a huge variety of cell behaviors
a cell’s response to a signal can be fast or slow
cell-surface receptors relay extracellular signals via intracellular signaling pathways
signals integrate -> physiological response
endocrine
hormones travel long distances to other parts of the body
insulin
travel short distances
growth factors
paracrine
neuronal
released by a nerve cell > stimulate a target cell
acetylcholine
contact dependent
direct cell-cell contact
antigen presentation
secrete products through ducts
onto epithelial surfaces (skin digestive tract)
extracellular effects (digestion of food)
mixed glands (liver, pancreas)
exocrine glands
no ducts
high density of capillaries (fenestrated)
secretions into bloodstream (internal secretions)
bind target cells
intracellular effects (alter metabolism)
endocrine glands
hybrid b/t neuron and endocrine cell
neuroendocrine cells
glands, tissues, and cells that secrete hormones
endocrine system
the study of this system and the diagnosis and treatment of its disorders
endocrinology
organs that are sources hormones
endocrine glands
no master endocrine control center
hypothalamus and pituitary gland
wide range of control
hypothalamus and pituitary gland
hunger and thirst
temperature homeostasis
sex drive
childbirth
stress response
hypothalamus
connected to hypothalamus (infundibulum)
pituitary gland
no neural connection to hypothalamus
capillaries (hypophyseal portal system)
anterior pituitary
hypothalamus hormones are brought to –>
anterior pituitary via bloodstream and regulate pituitary hormone secretion
nervous tissue; not a true gland
posterior pituitary
produce hormones
travel to post. pituitary
axons
stored in nerve endings
neuroendocrine cells of hypothalamus
6 hormones regulate
2 stored in
anterior pituitary; posterior pituitary
anterior associations:
releasing hormones
inhibiting hormones
names carry information for hormones
somatostatin (growth hormone)
promotes secretion of thyroid-stimulating hormone (TSH) and prolactin (PRL)
thyrotropin-releasing hormone (TRH)
promotes secretion of adrenocorticotropic hormone (ACTH)
corticotropin-releasing hormones (CRH)
promotes secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH)
gonadotropin-releasing hormone (GnRH)
promotes secretion of growth hormone (GH)
growth hormone-releasing hormone (GHRH)
inhibits secretion of prolactin (PRL)
prolactin-inhibiting hormone (PIH)
inhibits secretion of growth hormone (GH) and thyroid-stimulating hormone (TSH)
somatostatin
stimulated by: GnRH
target: ovaries and testes
follicle development
sperm production
follicle-stimulating hormone (FSH)
stimulated by: GnRH
target: ovaries and testes
ovulation -> corpus luteum
corpus luteum -> secretes progesterone
testes -> secret testosterone
luteinizing hormone (LH)
stimulated by: TRH
target: thyroid gland
thyroid gland growth
secretion of thyroid hormone (TH)
thyroid-stimulating hormone (TSH)
stimulated by CRH
target: adrenal gland (cortex)
increases release of gluccorticoids
regulates glucose, protein, fat metabolism
stress response
adrenocorticotropic hormone (ACTH)
stimulated by: TRH
target: mammary glands
stimulates milk production
prolactin (PRL)