LIFESCI 2 Chapter Notes - Chapter 42: Parathyroid Gland, Pineal Gland, Endocrine Gland
Document Summary
Major endocrine glands: pineal gland, hypothalamus, pituitary gland, parathyroid glands, thyroid gland, thymus gland, heart, stomach, adrenal gland, kidney, pancreas, small intestine, ovaries/testes. Mixed gland: part of the endocrine system as well as other organs. Chemical structure of hormones: hormones can be made of steroids (hydrophobic/lipophilic; membrane permeable) or peptides (hydrophilic/lipophobic; membrane impermeable) or amine (single modified amino acids; depends of amino acids, their synthesis and secretion vary. Hormones are synthesized in the ribosomes and rer as preprohormones and get converted to prohormone: preprohormone: inactive hormone. Packaged in golgi as prohormone: their chemical structure determines their mechanisms of action on target cell. Vesicle (to pass through the (cid:373)e(cid:373)(cid:271)ra(cid:374)e) e(cid:454)o(cid:272)(cid:455)tosis fro(cid:373) gla(cid:374)d i(cid:374)to (cid:271)lood free floati(cid:374)g through (cid:271)lood due to water solubility: steroid hormone. No vesi(cid:272)le e(cid:454)o(cid:272)(cid:455)tosis tra(cid:374)sport protei(cid:374) i(cid:374) (cid:271)lood takes in due to water insolubility. Mechanisms of steroids action of target cell: hormone can easily permeate the plasma membrane, receptor within cell.
