Endocrine System-Chapter 19 Flashcards
used for chronic regulation of homeostasis for a slow and prolonged response, integrated with nervous system by hypothalamus and posterior pituitary, hormones released into ECF and carried in blood stream
general characteristics of the endocrine system
hormones retained in interstitial fluid
paracrine signaling
blood carries hormones to other sites
endocrine signaling
substance synthesized by specific cell or tissue, secreted to act on target cells with specific receptors
hormones
steriods
non-polar (cholesterol)
peptides
polar
amines
(1) polar if from adrenal medulla
(2) non-polar if from thyroid
signal transduction is important because it _____________ the response
magnifies
composed of rings of C and H (cholesterol derivatives), non polar covalent bonds, can cross cell membrane, include estrogens, androgens, aldosterone, and cortisol
steroid hormones
short chains of amino acids, cannot cross cell membrane, water soluable for long travel
peptide hormones
derived from either tyrosine or tryptophan, come form adrenal medulla or thyroid, membrane insoluable from adrenal medulla (polar), membrane soluable if from thyroid (non-polar)
amine hormones
What are the steps to negative feedback?
(1) gland senses increase in [substance]
(2) gland stops secreting hormone
(3) decrease in [substance], hormone secretion increases
*results in relatively stable concentration of substance and hormone
What is the controller for homeostasis in all vertebrates?
the hypothalamus (sends signals to the body and the pituitary)
what is the most important endocrine gland for regulation?
the pituitary gland
The hypothalamus has endocrine or neural control over what parts of the body?
(1) endocrine control of anterior pituitary gland (hormones carried in hypophyseal portal system)
(2) neural control of posterior pituitary gland (same neurons of hypothalamus)
(3) neural control of adrenal medulla (preganglionic chain straight to chromaffin cells)
The pituitary gland is inferior to the hypothalamus and connected by the infundibulum. How are the 2 lobes of the pituitary gland different?
posterior- does not make any hormones, mostly hypothalamic axons
anterior- 5 types of endocrine cells (make stimulating hormones), include releasing hormones and inhibiting hormones
What are 2 hormones secreted by the posterior pituitary?
(1) antidiuretic hormone (ADH)-kidneys decrease water excretion
(2) oxytocin- contraction of uterine muscles, contraction of milk ejection
What are the hormones secreted by the anterior pituitary?
(1) melanocyte stimulation hormone (MSH)
(2) follice stimulating hormone (FSH)
(3) lutenizing hormone (LH)
(4) thyroid stimulating hormone (TSH)
(5) growth hormone (GH)
(6) prolactin (PRL)
(7) adrenocorticotropic hormone (ACTH)
anterior pituitary hormone that increases melanin secretion
melanocyte stimulating hormone (MSH)
anterior pituitary hormone that allows for follicular development in ovary and allows the testes to produce sperm, also stimulates the secretion of estrogen
follicular stimulating hormone (FSH)