Flashcards in [Chapter 32] Endocrine Control Deck (77)
Cell products secreted from endocrine glands, endocrine cells, and a few neurons. In most cases, bloodstream circulates hormones to target cells
Secreted by neurons into the tiny synaptic cleft between a neuron and a target cell
Local signaling molecules
Secreted by many cell types into extracellular fluid and broken down quickly; molecules only persist long enough to affect nearby tissues
Signals that diffuse through water or air to target cells in other individuals of the same species. Help integrate social behaviour (ex: female moth releases sex pheromone and attracts mate) Many vertabraes have vomeronasal organ in nose that responds to pheromones
When was the word hormone first used, what is its origin, and who coined it?
Early 1900s by physiologists W Bayliss and E Starling, from Greek word 'hormon', meaning 'to set in motion'
List the sources vertebrate hormones are (generally) secreted from
adrenal gland (2)
pancreatic islets (numerous cell clusters)
parathyroid gland (4 in humans)
endocrine cells of the hypothalamus, stomach, small intestine, liver, kidneys, heart, placenta, skin, adipose tissue, and other organs
All sources of hormones in the animal body, linked structurally and functionally with the nervous system in intercellular communication
How is the nervous system and the endocrine system linked?
Share a few structures, issue a few of the same signals, most organs accept and respond to signals from both.
In all animals, signaling molecules do what?
Integrate cell activities. each tupe of signal acts on all cells that have receptors for it. targeted cells may alter their activities in response.
Hypothalamus (part of the brain)
Produces, secretes six releasing and inhibiting hormones (act on different endocrine cells in anterior lobe of pituitary)
Produces ADH (conserves water) and oxytocin (roles in childbirth, milk secretion).
Pituitary gland, anterior lobe
ACTH, TSH, FSH, and LH (stimulate the secretion of other hormones), prolactine (affects mammary gland development), growth hormone (affects overall growth)
Pituitary gland, posterior lobe
Stores, secretes two hypothalamic hormones: ADH and oxytocin
Adrenal gland (one pair)
Cortisol (affects glucose metabolism) and aldosterone (conserves sodium)
Adrenal gland (one pair)
Epinephrine and norepinephrine (these hormones interact, in conert with the supathetic nervous system, to help adjust organ activities, especially during times of excitment or stress)
Ovaries (one pair of female gonads)
Estrogens and progesterone (maintain primary sex organs, influence secondary sexual traits)
Testes (one pair of male gonads)
Testosterone (develops and maintains primary sex organs, influences secondary sexual traits)
Melatonin (affects biological clocks, overall level of activity, reproductive cycles)
Thyroid hormone (affects growth and development, metabolism), calcitonin (lowers blood level of calcium)
Parathyroid glands (four)
Parathyroid hormone (increases blood level of calcium)
Thymosins (roles in white blood cell functioning)
Insulin (lowers blood level of glucouse), glucagon (raises blood level of glucose)
Hormones induce changes in service of programs of...
Growth, maintenance, and reproduction
Three steps of cell communication
Signal Reception (signal activates target cell receptor), signal transduction (transduced to a molecular form that acts in the receiving cell), cellular response (cell may make a functional response)
What do enzymes do?
Make hormones from a variety of sources
Steroid hormones are derived from?
ex: testosterone and other androgens, estrogens, progesterone, aldosterone, cortisol
Amine hormones are?
Modified amino acids
ex: melatonin, epinephrine, thyroid hormone
Peptide hormones are?
Short chains of amino acids
ex: glucagon, oxytocin, antidiuretic hormone, calcitonin, parathyoid hormone
Protein hormones are?
Longer chains of amino acids
ex: growth hormone, insulin, prolactin, follicle-stimulating hormone, luteinizing hormone
Signal response requires?