Question | Answer |
what does the PNS consist of? | 12 pairs of cranial and 31 pairs of spinal nerves |
what type of neurons carry messages to the brain? from the brain? | afferent, efferent |
describe a polarized cell | a cell with a charge difference on either side |
describe the depolarization of a cell | cell becomes more positive on the inside and more negative on the outside due to the movement of sodium into the cell |
describe the repolarization of a cell | the nerve impulse travels, allowing the cell to return to its original state |
what structures does the ANS control? | cardiac & smooth muscle, glands |
how many neurons are in the ANS pathway? | 2 |
how many neurons are in the SNS pathway? | 1 |
is the ANS excitatory or inhibitory? the SNS? | both, excitatory |
which neurotransmitters does the ANS release? | ACh and NE |
which neurotransmitter does the SNS release? | ACh |
the cell bodies of _____________ neurons are in the CNS | preganglionic |
describe the visceral efferent pathway | cell body in CNS->preganglionic fiber->postganglionic neuron->postganglionic fiber->effector |
name the true endocrine glands | pineal, hypophysis, thyroid, parathyroid, thymus, adrenals |
name the endocrine tissues | heart, lungs, stomach, kidneys, pancreas, ovaries, small intestine, testes, placenta, hypothalamus |
describe autocrine and paracrine hormones | autocrine hormones act on the secreting cell, paracrine hormones act on nearby cells |
describe amines | comprised of one type of amino acid, water soluble, manufactured in RER |
describe P&Ps | comprised of many amino acids, water soluble, manufactured in RER |
describe steroids | derived from cholesterol, lipid soluble, manufactured in SER |
describe eicosanoids | mimic-like hormones, comprised of fatty acids, derived from arachidonic acid (manufactured in the cell membrane of mammals) |
describe the physiology of hormone action | cell secretes hormone-> bloodstream-> protein receptor-> protein alteration & enzyme degradation-> alert secreting cell of status |
describe target cell receptors | specific proteins that accept hormones in a lock-key fit, numerous, up and down-regulate, down-regulation is more common |
describe the interaction with cell membrane receptors | hormone presence on membrane brings a chemical message-> G protein activation-> adenylate cyclase activation-> ATP split-> ADP release-> cAMP stimulates enzymatic change-> cAMP activates protein kinases-> kinases add free Ps (phosphorylation) |
describe the interaction with intracellular receptors | hormone attaches to receptor, forming hormone-receptor complex-> binds to chromatin-> alters mRNA-> mRNA carries message to synthesize new protein-> tRNA assembles protein |
describe how hormones interact with each other | permissively: one paves the way for another, synergistically: work together, antagonistically: one opposes another |
this type of feedback has a stimulatory-inhibitory effect | negative |
this type of feedback has a stimulatory-stimulatory effect | positive |
describe the three modes of negative feedback controlling hormonal secretions | hormonal: hormones control other hormones, humeral: blood levels control hormone secretion, neural:nerve impulses control hormone secretion |
name and describe the two hormones secreted by the pineal gland | melatonin: induces sleep, inhibits gonadotropic hormones, enhances lymphocytic ability
adrenoglomerulotropin: stimulates zona glomerulosa of the adrenal cortex |
name the five troph cells of the adenohypophysis and the hormones they secrete | somatotroph:hGH, lactotroph:PRL, thyrotroph:TSH, gonadotroph:FSH and LH, corticotroph:MSH and ACTH |
how is troph cell secretion controlled? | releasing and inhibiting factors of the hypothalamus |
describe what makes a hormone tropic | has releasing factors only |
describe how regulating factors travel from the hypothalamus to the adenohypophysis | low levels-> brain-> hypothalamus-> regulating factor to primary plexus-> hypophyseal portal veins to secondary plexus-> diffusion to bloodstream->adenohypophyseal hormone secreted by troph cell-> diffusion into secondary plexus->anterior hypophyseal vein |
describe the inguinal canals | openings in the abdomino-pelvic cavity that allow testicular descent, communication with the body proper, and passage of the cremaster muscle |
what structures are contained within the spermatic cord? | vas deferens, blood and lymph vessels, nerves |
describe the tunica albuginea | inverts to form 200-300 lobules, which each contain 1-3 seminiferous tubules |
describe spermatogenesis | spermatogonium-> primary spermatocyte-> secondary spermatocytes-> spermatids-> spermatozoa |
describe the epididymis | an organ in the posterior testes that serves as the maturation site for spermatozoa (2 weeks). has a head, body, and tail. |
describe seminal vesicle fluid | 60% of semen, alkaline, increases sperm motility, composed of fructose (ATP), prostaglandins (muscle contraction) & fibrinogen (thickener) |
describe prostatic fluid | 20-30% of semen, acidic, gives milky appearance, protects from UTIs (seminalplasmin), comprised of coagulating&liquifying enzymes |
describe cowper's fluid | <5% of semen, alkaline, mucus to protect sperm |
describe semen | pH 7.2-7.6, composed of sperm, prostatic cowper's and seminal vesicle fluids |
describe sperm | has a head that dissolves oocyte, neck that produces ATP, and flagellum for movement |
describe the hypothalamic hormone that affects the male reproductive system | GnRH: regulates the secretion of the gonadotroph (adenohypophyseal) cell |
describe the adenohypophyseal hormones that affect the male reproductive system | FSH: encourages spermatognesis, LH: increases testosterone |
describe inhibin in a male | P&P, secreted by nurse cells, temporarily inhibits FSH to decrease spermatogenesis |
describe testosterone | steroid, secreted by interstital endocrinocytes, maintains sex characteristics and works as a protein anabolist |
describe hGH | non-tropic P&P, secreted by somatotroph cell, is a lipid/carb catabolist and protein anabolist |
what hormone imbalance cause gigantism? | too much hGH in children |
what hormone imbalance causes acromegaly? | too much hGH in adults |
what hormone imbalance causes progeria? | too little hGH in adults |
what hormone imbalance causes dwarfism? | too little hGH in children |
name the factors that influence and inhibit hGH release | influence: high amino acids, low glucose, low fatty acids
inhibit: low amino acids, high glucose, high fatty acids |
describe PRL | non-tropic P&P, secreted by lactotroph cell, acts on alveoli to produce milk |
describe how PRL affects males | it doesn't, other than erectile dysfunction with hypersecretion |
describe how PRL affects females | depends on estrogen (increase causes PRL decrease), causes milk production |
what does the hyposecretion of PRL cause? | decreased milk production, affects only the nursing mother |
what does the hypersecretion of PRL cause? | erectile dysfunction in men, galactorrhea/amenorrhea/infertility in women |
describe TSH | tropic P&P, secreted by the thyrotroph cell, stimulates thyroid to produce T3 and T4 |
describe FSH | tropic P&P, controlled by GnRH |
describe how FSH affects males and females | males: increases spermatogenesis, females: oogenesis, increased estrogen secretion |
describe LH | tropic P&P, controlled by GnRH |
describe how LH affects males and females | males: increases testosterone release, females: allows ovulation, increases progesterone and decreases estrogen with pregnancy |
describe MSH | non-tropic P&P, affects skin pigmentation |
describe ACTH | tropic P&P, acts on zona fasiculata to increase cortisol secretion, regulated by CRH |
describe CRH | P&P, neurotransmitter as well as hormone
stress-> increase CRH-> increase ACTH-> stimulate zona fasiculata-> increase cortisol |
where are neurohypophyseal hormones released into the bloodstream? | plexus of infundibular process |
describe the formation of T3 and T4 | iodine converted to iodide-> blood stream to thyroid-> reconverted to iodine by thyroid peroxidase-> cell lumen to combine with tyrosine-> thyroid hormone |
name the protein carrier that allows the transport of T3 and T4 | TBG |
why might the hypersecretion of ADH occur? | tumor, meningitis, neurosurgery, general anesthesia, SIADH |
what are oxytocics used for? | stimulate contractions, milk letdown, prevent postpartum hemorrhage |
what is the carrier protein associated with OT and ADH? | neurophysin |
describe OT | P&P, produced by hypothalamus but secreted by neurohypophysis, stimulates milk letdown, uterine contractions, and prevents postpartum hemorrhage |
what issues are associated with the hyposecretion of ADH? | head trauma, diabetes insipidus |
what factors inhibit ADH? | edema, high water intake, caffeine, diuretics |
what factors stimulate ADH? | dehydration, low blood pressure, low fluid intake |
describe ADH | P&P, prevents swings in water balance, acts on sweat glands/principal cells of DCT/salivary glands/blood vessels |
what secretes CT? | parafollicular cells of the thyroid |
describe TGB | manufactured in the RER of the follicular cells of the thyroid, houses tyrosine |
in what disease does hyperthyroidism result and how may it be treated? | graves; thyroidectomy, destruction of thyroid tissue, antithyroid drugs |
how does hypothyroidism manifest in children? in adults? how can these conditions be treated? | cretinism, myxedema; thyroid drugs |
describe CT | P&P, secreted by C cells of the thyroid, decreases blood calcium by stimulating osteoblastic activity (pulls calcium into cell) |
what is the general function of thyroid hormones? | organic metabolic balance |
describe PTH | P&P, increases calcium blood levels, by stimulating osteoclastic activity |
describe calcitriol | needed for calcium absorption, stimulated by PTH, acts on kidney&GI tract |
what causes hyperparathyroidism and how does it manifest? | too much blood Ca; bone pain, fatigue, weak contraction, kidney stones, decreased nervous system activity |
what causes hypoparathyroidism and how does it manifest? | too little blood Ca; bone spurs, twitches, convulsions, respiratory paralysis, death |
describe thymosin | P&P, produced by the thymus, stimulates maturation of T cells |
where are mineralcorticoids manufactured and what is the major one? | zona glomerulosa, aldosterone |
where are glucocorticoids manufactured and what the the major one? | zona fasciculata, cortisol |
where are gonadocorticoids manufactured and what is the major one? | zona reticularis, testosterone with a little estrogen |
describe chromaffin cells | modified postganglionic neurons, manufacture and secrete E (80%) and NE (20%) , located near blood sinuses |
describe E | increases heart rate, sweating, respiratory rate, and glycogenolysis |
describe NE | influences vasoconstriction |
describe the renin-angiotensin pathway | low BP-> JGA releases renin-> blood to liver-> renin+angiotensin-> angiotensin 1 to lung-> angiotensin 1+ACE-> angiotensin 2 |
describe aldosterone | steroid, secreted by zona glomerulosa, stimulates sodium resorption and elimination of potassium |
what structures does aldosterone act on? | sweat glands, salivary glands, gastric secretions, principal cells of DCT |
what is the urine tested for when a pheochromocytoma is suspected? | VMA |
what effects does the formation of angiotensin II have? | increases thirst, stimulates ADAH secretion, vasoconstriction, stimulates aldosterone secretion |
what stimulates the secretion of aldosterone? | low sodium, high potassium |
what inhibits the secretion of aldosterone? | high sodium, low potassium, ANF |
describe ANF | P&P, secreted in response to increased atrial blood volume, inhibits ADH and aldosterone to decrease blood volume |
what disease is associated with hypoaldosteronism? | addison's |
describe cortisol | steroid, secreted by zona fasiculata, increases blood glucose to combat stress, breaks down carbs and fats to convert to glucose (gluconeogenesis) |
describe the control of cortisol secretion | stress-> CRH stimulation-> ACTH stimulation->zona fasiculata stimulation-> release |
what disease is associated with the hypersecretion of cortisol? | cushing's |
describe gonadocorticoids | steroids, secreted by zona reticularis, contribute to puberty onset |
name the three stages of GAS | alarm (FFF initiated), resistance (hypothalamic hormone intervention), exhaustion (system collapse) |
describe the four types of cells in the islets of langerhans | alpha-secretes glucagon; beta-secretes insulin; delta-secretes somatostatin; f cell-secretes pancreatic polypeptide |
describe glucagon | P&P, raises blood glucose through glycogenolysis, monitored by alpha&beta cells of the pancreas |
what stimulates glucagon release? inhibits? | low blood glucose; high blood glucose, somatostatin |
describe insulin | P&P, decreases blood glucose by increasing cellular uptake of glucose |
describe somatostatin | P&P, inhibits glucagon and insulin to crrate balance, slows GI absorption |
describe pancreatic polypeptide | P&P, stimulates production of pancreatic juice, influences GI absorption |
describe type 1 diabetes | caused by not enough functioning beta cells/viruses/auto-immune response, causes weight loss and urine ketones |
describe type 2 diabetes | down-regulation of insulin receptors, tumor necrosis factor alpha produced by fat-> decreases Glut 4-> decreased cellular uptake |
describe hCG | P&P, secreted by trophoblast, tells corpus luteum to continue progesterone secretion and halt estrogen secretions to maintain the placenta |
describe hCS | P&P, secreted by chorion, encourages breast tissue development |
describe hCT | P&P, secreted by chorion, increases maternal metabolism |
describe relaxin | P&P, secreted by corpus luteum and placenta, loosens the hips and starts cervical dilation |
describe inhibin as related to the female reproductive system | P&P, secreted by corpus luteum, inhibits FSH at the end of the period |
describe progesterone | steroid, secreted by corpus luteum, increases uterine lining and breast development |
describe estrogen | steroid, secreted by theca cells, maintains sex characteristics, is a protein anabolist, is a water balancer |
describe GnRH | secreted from hypothalamus, controls gonadotroph cell (PRH and PIH) |
describe the mammary glands | supported by Cooper's ligament, produces milk in alveoli-> secondary tubules-> mammary ducts-> lactiferous ducts-> nipple |
where do the skene's glands lie? | surrounding the urethral orifice |
describe the blood supply of the uterus | aorta-> uterine arteries-> arcuate arteries (perimetrium)-> radial arteries (myometrium)-> straight (stratum basalis) and spiral arteriole(stratum functionalis) |
describe the tissue layers of the uterus, outer to inner | perimetrium: protection, myometrium: muscle, endometrium: stratum basalis (permanent, manufactures stratum functionalis), stratum functionalis (temporary) |
describe the terminal ganglia | serviced by parasympathetic preganglionic neurons of the craniosacral division |
describe the prevertebral ganglia | serviced by sympathetic preganglionic neurons of the thoracolumbar division |
describe the sympathetic trunks | vertical to the sides of the vertebral column, run from the skull to the coccyx |