Introduction to Endocrine Systems Flashcards
what is endocrine transmission?
chemical secreted in low concentrations by a cell or group of cells sent to all parts of the body via the bloodstream
what needs to be present for a hormone to act on a cell?
the correct membrane receptor protein
describe humoral communication
many cells in different parts of body, coordinated body-wide actions, slow to act but effect persists
what are the different endocrine glands?
hypothalamus, pituitary gland, thyroid gland, parathyroid gland, pancreas, adrenal glands, endocrine cells in GI tracts, ovaries and testes, placenta, pineal gland and thymus
what are the two types of hormones?
steroids and non-steroids
what are the non-steroid hormones?
amino acid derivatives, peptides, glycoproteins
what are steroid hormones based on?
cholesterol ring structure
what are the different types of steroid hormones?
cortisol, aldosterone, testosterone, oestrogen, progesterone
what are the two classes of amino acid derivatives?
amines and iodinated amino acids
what are the different amines?
adrenaline (epinephrine), noradrenaline (norepinephrine), melatonin
what are the different iodinated amino acids?
tri-iodo-thyronine (thyroxine) and tetra-iodo-thyronine
name some different peptides
short chain, long chain, growth hormone, prolactin, parathyroid, calcitonin, adrenocorticotropic, insulin, glucagon, G.I tract hormones (secretin, CCK, gastrin)
what are pro-hormones
they are an inactive, precursor form of a peptide hormone
what produces the pro-hormone in the endoplasmic reticulum
pre-pro-hormone
where is the pro-hormone packaged and what does it turn into?
it is packaged in the golgi apparatus and is converted into the active hormone
what happens once an active hormone is produced in the golgi apparatus?
it is secreted
what do glycoproteins possess?
carbohydrate groups attached to the amino acids
name the different glycoproteins
follicle stimulating hormone, luteinizing hormone, thyroid stimulating hormone, chorionic gonadotrophin
what are the local tissue hormones
prostaglandins, leukotrienes, thromboxanes
what are the functions of local tissue hormones?
regulation of blood flow, homeostasis, mucosal protection, inflammation
name 2 common second messengers
cyclic AMP and calcium ions
how do steroid hormones reach intra-cellular receptors?
they pass through the outer cell membrane
summarise the actions of hormones
synthesis/storage, release in response to stimulus, transport in blood, action on target cells (role of 2nd messengers), metabolism/excretion
what type of hormones use second messengers?
non-steroid hormones
