Term
| endocrine glands (characteristics) |
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Definition
1. ductless
2. secrete hormones into the blood
3. organs secrete hormones too |
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Term
| 4 chemical classifications of hormones |
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Definition
1. amines
2. polypeptides and proteins
3. glycoproteins
4. steroids |
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Term
| polypeptides and proteins |
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Definition
1. hormone
examples: antidiuretic hormone, insulin, growth hormone |
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Term
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Definition
1. derived from tryosine and tryptophan
examples: hormones from the adrenal medulla, thyroid and pineal glands |
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Term
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Definition
1. long polypeptides bound to a carbohydrate
examples: follicle-stimulating and luteinizing hormones |
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Term
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Definition
1. lipids derived from cholesterol
2. secreted by adrenal cortex and gonads
examples: testosterone, estradiol, progresterone, cortisol |
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Term
| 2 hormone classifications |
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Definition
1. polar hormones
2. nonpolar hormones |
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Term
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Definition
1. water soluble
2. cannot pass through plasma membranes
3. injected if used as a drug |
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Term
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Definition
1. insoluble in water
2. can enter target cells directly
3. often called lipophilic hormones
4. include steroids and thyroid hormone
5. can be taken orally in pill form |
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Term
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Definition
1. made before the hormone
2. inactive hormones that must be cut and spliced together to be active |
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Term
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Definition
1. made before the hormone
2. inactive hormones that must be modified within their target cells |
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Term
| hormones vs. neurotransmitters |
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Definition
1. both interact with specific receptors
2. binding to a receptor causes a change within a cell |
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Term
| hormone interactions (3 aspects) |
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Definition
1. a target cell is responsive to several different hormones
2. hormones may be antagonistic, synergistic or permissive
3. how a cell responds depends on the amount of hormone and the combination of all hormones |
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Term
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Definition
1. two or more hormones work together to produce a particular effect
2. can be "additive" or "complementary" |
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Term
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Definition
1. one hormone makes the target cell more responsive to a second hormone
(estrogen and progresterone in the uterus) |
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Term
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Definition
1. hormones work in opposite directions
(insulin stimulates fat storage; glucagon stimulates fat breakdown) |
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Term
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Definition
1. ranges from minutes to hours
2. removed from the blood by the liver
(thyroid hormone circulates for several days) |
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Term
up-regulation of hormones
(priming effects) |
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Definition
1. target cells increase the number of receptors it has for a hormone
2. makes it more sensitive to subsequent hormone release |
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Term
down-regulation of hormones
(desensitization) |
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Definition
1. prolonged exposure to high concentrations of hormone may result in decreased number of receptors for that hormone
2. many hormones are released in spurts to avoid desensitization = called PULSATILE SECRETION |
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Term
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Definition
1. bind to receptors ON or IN target cells
2. highly specific binding
3. hormones bind to receptors with a high affinity
4. hormones bind to receptors with a low capacity |
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Term
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Definition
1. activate genetic transcription by serving as transcription factors
2. produce new proteins (enzymes) that change the metabolism inside the cell
3. after binding, they translocate to the nucleus and bind to DNA |
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Term
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Definition
1. thyroxine travels to target cells on thyroxine-binding globulin (TBG)
2. inside the target cell, it's converted to T3
3. receptor proteins are located inside the nucleus bound to DNA |
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Term
| coactivators and corepressors |
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Definition
1. molecules are needed in addition to the steroid hormone
2. they bind to the nuclear receptor proteins at specific regions
3. this changes the effect of a given hormone in different cells |
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Term
| hormones that use 2nd messengers |
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Definition
1. can't cross the plasma membrane, so they bind to receptors on the cell surface
(epinephrine, norepinephrine, insulin) |
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Term
| 2nd messenger: Adenylate Cyclase/cAMP |
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Definition
| 1. used by epinephrine and norepinephrine |
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Term
| 2nd messenger: Phospholipase C |
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Definition
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Term
| 2nd messenger: Tyrosine Kinase |
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Definition
1. used by insulin
2. the receptor is also the enzyme tyrosine kinase (ligand-binding site on cell)
3. enzyme activated by phosphorylation |
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Term
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Definition
1. attached to the hypothalamus
2. divided into anterior and posterior lobe |
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Term
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Definition
1. secreted by anterior lobe
2. trophic hormones stimulate hormone secretion in other glands |
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Term
| hormones in other glands affected by pituitary hormone secretion |
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Definition
1. growth hormone (GH)
2. thyroid-stimulating hormone (TSH)
3. adenocorticotropic hormone (ACTH)
4. follicile-stimulating hormone (FSH)
5. lutenizing hormone (LH)
6. prolactin (PRL) |
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Term
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Definition
1. stores and releases two hormones:
ADH - promotes water retention in kidneys
Oxytocin - stimulates contractions in childbirth |
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Term
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Definition
1. atop the kidneys
2. outer adrenal cortex and inner adrenal medulla |
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Term
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Definition
| 1. secretes epinephrine and norepinephrine in response to neural stimulation from hypothalamus |
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Term
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Definition
| 1. secretes steroid hormones in response to ACTH |
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Term
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Definition
1. made from cholesterol
2. three categories: mineralocorticoids, glucocorticoids, sex steroids |
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Term
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Definition
| regulate Na+ and K+ balance |
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Term
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Definition
| regulate glucose metabolism (cortisol) |
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Term
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Definition
| weak androgens that supplement those made in the gonads |
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Term
| stress and the adrenal gland |
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Definition
1. stress increases secretion of ACTH, which results in increased glucocorticoid release
2. "general adaptation syndrome" |
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Term
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Definition
1. helps inhibit the immune system so that it does not overrespond
2. acts on higher brain regions; contributes to depression and anxiety |
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Term
| general adaptation syndrome |
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Definition
| 3 stages: alarm, resistance, exhaustion |
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Term
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Definition
| 1. cube shaped, one layer |
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Term
| thyroid hormone production |
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Definition
| 1. thyroglobulin is made by follicular cells |
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Term
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Definition
1. stimulates protein synthesis
2. promotes maturation of the nervous system
3. increases rates of cellular respiration
4. elevates basal metabolic rate |
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Term
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Definition
1. made by parafollicular cells
2. inhibits dissolution of bone calcium
3. stimulates calcium excretion in the kidneys to lower blood calcium levels |
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Term
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Definition
1. low metabolic rates
2. weight gain and lethargy
3. poor adaptation to cold stress
4. myxedema (fluid accumulation) |
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Term
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Definition
1. overstimulation of thyroid gland
2. goiter |
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Term
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Definition
thyroid: decreases calcium
parathyroid: increases calcium |
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Term
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Definition
1. endocrine and exocrine gland
2. endocrine cells are in Islets of Langerhans
3. exocrine glands deal with digestion |
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Term
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Definition
1. alpha cells: glucagon
2. beta cells: insulin |
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Term
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Definition
1. takes glucose out of the blood
2. purpose is to lower blood glucose levels to the normal range
3. secreted by beta cells when glucose levels rise after sugary meals |
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Term
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Definition
1. binds to receptors on target cells
2. indirectly stimulates the enzyme glycogen synthase in the liver and skeletal muscles to promote sugar storage
3. stimulates adipose tissue to store fat |
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Term
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Definition
1. antagonistic to insulin
2. secreted by alpha cells when glucose is low
3. raises blood glucose levels to normal |
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Term
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Definition
1. stimulates gluconeogenesis (noncarbs to glucose)
2. stimuluates lipolysis in adipose tissue (fat is released and used instead of glucose)
3. stimulates liver to hydrolyze glucagon into glucose and release it into the blood |
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Term
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Definition
1. located on roof of third ventricle in the brain
2. secretes the hormone melatonin (circadian rhythms)
3. regulated by the hypothalamus (stimulates melatonin production when it gets dark) |
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Term
| autocrine vs. paracrine signals |
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Definition
| 1. both involved in short-range signaling between neighboring cells within an organ |
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Term
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Definition
1. sender and receiver are the same cell type
2. regulatory molecules are called CYTOKINES or growth factors
3. most control gene expression in the target cell |
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Term
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Definition
| 1. sender and receiver are different cell types/tissues |
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Term
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Definition
1. group of autocrine regulators
2. made from arachidonic acid released from phospholipids in the plasma membrane
3. released from almost every cell
4. wide range of function |
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Term
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Definition
1. immune system: promote inflammation
2. reproductive system: aid ovulation
3. digestive system: inhibit secretion, stimulate absorption
4. respiratory system: aid bronchoconstriction and dilation
5. circulation: vasoconstriction, dialation, blood clotting
6. urinary system: increase blood flow to the kidneys |
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