endocrine system Flashcards
Hormones may be amino acid derivatives, peptides, or lipid derivatives. Thyroid hormones are amino acid derivatives. _______ include epinephrine, norepinephrine, and dopamine. Melatonin is a _______ derivative.
Catecholamines, tryptophan
Peptide hormones are the most numerous hormones in the body. Peptide hormones can be short polypeptide chains all the way to smaller ______. _______ are polypeptides with carbohydrate side chains such as TSH, LH, FSH (released by anterior pituitary) which can serve a hormonal function.
proteins, Glycoproteins
_______ are fatty acids with important paracrine factors that coordinate cellular activity, innate immune responses and enzymatic processes in extracellular fluid.
Eicosanoids
Steroids are lipid soluble hormones bound to specific transport proteins in blood. Steroids remain in circulation _____ than peptide hormones. Steroids are released by ______ organs. Steroid hormones include androgens in males and estrogen/progesterone in females.
longer, reproductive
Adrenal glands release ______ and kidneys release ______ (hormone from Vitamin D)
corticosteroids, calcitriol
Hormones only affect specific target tissues with specific _____. The receptors themselves are constantly synthesized and broken down. Down regulation is a decrease in receptors on target cells. Down regulation is a response to _____ hormone levels. Up regulation is an increase in receptors on target cells. Up regulation is a response to _____ hormone levels.
receptors, high, low
Hormones are long distance chemical signals traveling in blood or lymph. _______ signaling causes chemicals that exert effects on same cells that secrete them. ______ signaling causes locally acting chemicals to affect cells other than those that secrete them.
Autocrine, Paracrine
Amino acid base hormones are water soluble and act on plasma membrane receptors. Amino acid base hormones _____ enter cells. Steroids are lipid soluble hormones synthesized from cholesterol. Steroids _____ enter cells due to their lipid profile. Lipid soluble hormones (steroids) bind to receptors inside target cells while water soluble hormones bind to receptors on plasma membrane. Water soluble hormones activate a ______ messenger system, an amplification of its original small signal that delivers itself intracellularly.
can’t, can, second
Receptors are on plasma membrane. Hormones act as first messenger. Relay message to intracellular second messenger. The second messenger then effects enzyme (catalyst) activity and changes cellular metabolic reactions, creating the hormone’s effect on the cell. Examples of second messengers include cyclic AMP and calcium ions. Usually involves a G protein (glycoprotein). Enzyme complex is coupled to receptor.
water soluble protein
Receptors are in cytoplasm or nucleus (intracellular receptors). Lipid soluble- can diffuse through plasma membrane, altering the activity of specific genes. Changes protein synthesis or the synthesis of enzymes and structural proteins, affecting cell’s metabolic activity and structure.
steroid hormones
Thyroid hormones are water soluble amino acid proteins able to be transported across cell membrane by _______ _______processes. Binds to receptors on ________, increasing rate of ATP production. Binds to receptors in ______ activating specific genes or change rate of protein synthesis.
carrier mediated, mitochondria, nucleus
___________ is when one hormone can’t work without another hormone present, like thyroid and sex hormones. ___________ is more than one hormone that produces same effects on target cells causing amplification, such as glucagon and epinephrine causes liver to release glucose. _________ is one or more hormones oppose action of another hormone, like insulin and glucagon.
Permissiveness, Synergism, Antagonism
Hormone release is mostly controlled by negative feedback systems. _______ stimuli refer to changes of ions and nutrients (e.g. calcium levels) in blood or extracellular fluid. ______ stimuli are nerve fibers stimulating hormone release. An example of this stimuli can be sympathetic nervous system stimulate adrenal medulla to secrete catecholamines. ________ stimuli refer to hormones stimulating other endocrine organs to release their hormones. An example of this stimuli is hypothalamic hormones stimulate anterior pituitary hormones.
Humoral, Neural, Hormonal
Axon terminals of neurons from hypothalamic neurons produce the two hormones oxytocin and anti-diuretic hormone (ADH). Transported by ________ _____ system to the posterior pituitary.
hypophyseal portal
The hypothalamus contains _________ that monitor solute concentrations, which ultimately monitor water. High solute concentrations are correlated with low water levels. The posterior pituitary can send a signal to kidney tubules to reabsorb more water by preventing urine formation.
osmoreceptors
