Question | Answer |
the nervous system and the endocrine system function together to | monitor and adjust physiological activities for the regulation of homeostasis |
homeostasis is the maintenance of a | relatively constant internal environment |
the regulatory effects of the endocrine system are...compared to the... | long-term ongoing metabolic processes...short-term effects of the nervous system |
endocrine organs are..into... | ductless glands that release hormones...blood or lymph |
hormones are | messenger molecules that travel in the circulatory vessels and signal phsyiological changes in target cells |
hormonally regulated processes include | reproduction, growth, mobilization of body defenses against stress, maintenance of the proper chemistry of the blood and body fluids and regulation of cellular metabolism |
the endocrine organs are | small and widely separated from one another within the body |
the pure endocrine organs are the | pituitary, thyroid, parathyroid, adrenal, and pineal glands |
other organs that contain endocrine cells are the | gonads, pancreas, kidney, alimentary canal, heart, thymus and skin |
the hypothalamus of the brain is a | neuroendocrine organ |
endocrine organs are richly | vascularized |
although most endocrine cells are | modified epithelial cells, others are neurons, muscle cells, or fibroblast-like cells |
most hormones are either | amino acid derivatives or steriods |
amino acid derivates include | amines, peptides and proteins |
steroids are | lipid based molecules derived from cholesterol |
hormones produce their effects by leaving the | capillaries and binding to specific receptor molecules in or on their target cells |
such binding triggers a | preprogrammed response in the target cell |
endocrine organs are stimulated to release their hormones by | humoral, neural or hormonal stimuli |
hormonal secretion is controlled by | feedback loops |
the hypothalamus of the brain regulates | many functions of the endocrine system through the hormones it secretes |
the golf club-shaped...is suspended from the | pituitary gland...diencephalon of the brain by its stalk (infundibulum) |
the pituitary gland lies in the | hypophyseal fossa of the sella turcica of the sphenoid bone |
the pituitary gland consists of an | anterior adenohypophysis and a posterior neurohypophysis |
the anterior adenohypophysis has three pars | pars distalis, pars intermdedia, pas tuberalis |
pars distalis (anterior lobe) is the | largest, anteriormost part of the adenohypophysis |
cells in the pars distalis cluster into | spheres and branching cords |
the five cell types of the pars distalis secrete | seven protein hormones |
somatotropic cells secrete...and are the most | growth hormone...abundant cells in the pars distalis |
mammotropic cells secrete | prolactin |
thyrotropic cells secrete | thryoid stimulating hormone |
corticotropic cells secrete | adrenocorticotropic hormone and melanocyte-stimulating hormone |
gonadotropic cells secrete | follicle stimulating hormone and luteinizing hormone |
growth hormone (somatotropic) stimulates | growth of the body and skeleton |
prolactin signals | milk production |
thyrotropic signals the | thyroid gland to secrete thyroid hormone |
adrenocorticotropic signals the | adrenal cortex to secrete glucocorticoids |
melanocyte-stimulating hormone causes the | skin to darken |
follicle stimulating hormone and luteinizing hormone together are called | gonadotropins |
gonadotropins signal the | maturation of sex cells and the secretion of sex hormones |
four of the seven hormones (FSH, LH, ACTH, TSH) stimulate | other endocrine glands to secrete and are called tropic hormones |
pars intermedia is located just | posterior to pars distalis |
pars tuberalis is located just | superior to pars intermedia, and wraps around the infundibulum like a tube |
the posterior neurohypophysis also has three pars | pars nervosa, infundibular stalk, median eminence |
pars nervosa is the | inferiormost part of the neurohypophysis |
median eminence is the... | cone shaped portion of the hypothalamus |
the neurohypophysis does NOT ...it only | make hormones...stores and releases hormones produced in the hypothalamus |
the pituitary hypophyseal artery supplies the | entire adenohypophysis and the infundibulum |
the inferior hypophyseal artery supplies the | pars nervosa |
the hypothalamus of the brain controls the | secretion of hormones from the adenohypophysis |
hypothalamus controls the secretion of hormones from the adenohypophysis in the following manner: first, certain hypothalamic nuerons make | releasing hormones and inhibiting hormones, which they secrete into primary capillary plexus in the median eminence |
the releasing hormones and inhibiting hormones then travel through...to a... | hypophyseal portal veins...secondary capillary plexus in the pars distalis |
the hormones then leave this plexus to signal...which then enter the... | the adenohypophyseal cells to secrete their hormones...secondary capillary plexus and travel to their target cells throughout the body |
the neurohypophsis consits of...which contains the... | nervous tissue...hypothalamic hypophyseal axon tract |
the cell bodies of the neurons that form the hypothalamic-hypophyseal axon tract are located in the | paraventricular and supraoptic nuclei of the hypothalamus |
the cell bodies of the neurons that form the tract synthesize...and store them in their | oxtyocin and ADH...axon terminals in the pars nervosa |
the stored hormones in the neurons of the hypothalamic-hypophseal axon tract are then | released into capillaries when the neurons fire |
ADH increases | resorption of water from the urine and raises blood pressure |
oxytocin induces | labor and ejection of milk from the breasts |
ADH and oxytocin are involved with | social bonding |
the thyroid gland, which lies on the...consists of... | superior trachea...spherical follicles covered by epithelial follicle cells and separated by a capillary rich CT |
thyroid follicles are filled with a | colloid of thyroglobulin |
thyroglobulin is a | storage protein containing thyroid hromone |
thryoid hormone, which contains...is made continuously by... | iodine and increases basal metabolic rate...follicle cells |
thyroid hormone is stored within the...until... | follicles...TSH from the pituitary gland signals the follicle cells to reclaim the TH and secrete it into the extrafollicular capillaries |
parafollicular cells protrude from the ...and secrete the hormone... | thyroid follicles...calcitonin |
calcitonin can | lower blood calcium concentrations in children |
several pairs of parathyroid glands lie on the | dorsal aspect of the thyroid gland |
the chief parathyroid cells are arranged in...and secrete.. | thick, branching cords...parathyroid hormone |
parathyroid hormone | raises low blood calcium levels |
the paired adrenal glands lie on the | superior surface of each kidney |
each adrenal gland has two distinct parts, an | outer cortex and an inner medulla |
the adrenal medulla consists of | sperical clusters of chromaffin cells |
upon sympathetic stimulation, these chromaffin cells secrete | epinephrine and norepinephrine into the blood |
the adrenal cortex has three layers, the | zona glomerulosa, fasciculata, reticularis |
outer zona glomerulosa contains cells arranged in | spherical clusters |
middle zona fasciculata's cells are arranged in | parallel cords |
inner zona reticularis' cells are arranged in a | branching network |
the steriod hormones secreted by the...include... | adrenal cortex...mineralocorticoids, glucocorticoids, and dihydroepiandrosterone, DHEA |
mineralocorticoids from the...conserve...by... | zona glomerulosa...water and sodium...increasing resorption of these substances by the kidney |
glucocorticoids from the...help the body...by... | zona fasciculata and reticularis...cope with stress...stabilizing blood glucose levels |
in large quantities, glucocorticoids also | inhibit inflammation in the immune system |
the androgen dihydroepiandrosterone, DHEA from the...has...functions but they are probably... | zona reticularis...unclear...beneficial |
steriod-secreting cells, including the cells in the...have an abundant... | gonads that secrete sex hormones...SER, tubular cristae in their mitochondria, abundant lipid droplets, and no secretory granules |
the pineal gland, on the roof of the...contains | diencephalon..pinealocytes |
pinealocytes cluster into | spherical clumps and cordsd separated by dense particles of calcium called pineal sand |
pinealocytes secrete the hormone | melatonin |
melatonin helps | regulate circadian rhythms |
pnealocyte secretion is signaled by the | suprachiasmtic nucleus of the hypothalamus through a sympathetic pathway |
the endocrine structures in the pancrease the the | spherical pancreatic islets |
the islets contain | alpha, beta, delta, and F cells |
islet cells are arranged in | twisting cords |
alpha cells secrete | glucagon |
glucagon raises | blood sugar levels |
beta cells secrete | insulin which lowers blood sugar levels |
the thymus is an important organ of the | immune system |
the thymus secretes | thymic hormones which are essential for the production of T lymphocytes |
various cells in the ovaries and testes secrete | steriod sex hormones, estrogens, and androgens |
some muscle cells in the atria of the heart secrete | atrial natriuretic peptide |
ANP stimulates loss of | body fluids and salts through the production of a sodium-rich urine |
endocrine cells are | scattered within the epithelium of the digestive tract and other gut-derived organs |
the epithelial cells, which have some...properties, make up the... | neuron-like...diffuse neuroendocrine system |
there are many classes of...cells, some of which secrete hormones that ... | diffuse neuroendocrine system...regulate digestion |
the placenta secretes hormones of | pregnancy |
the kidney secretes | rennin and erythropoietin |
the skin produces | vitamin D |