A&P II: Endocrine System
what is a function of catecholamines?
a. increase alertness, and prepare the body for physical activity
the pituitary gland is composed of two structures: the posterior lobe is called the neurohypophysis and the anterior lobe is called the_______
adenohypophysis
leptin is synthesized by _______.
adipocytes
what is the target organ for the adrenocorticotropic hormone?
adrenal cortex
which structure is yellow in color due to its high lipid content and produces steroid hormones from cholesterol?
adrenal cortex
region indicated by the red arrow:
adrenal medulla
which structure acts as both an endocrine gland and as a ganglion of the sympathetic nervous system?
adrenal medulla
which hormone stimulates the release of glucocorticoids?
adrenocorticotropic hormone
_______ syndrome, the. hypersecretion of adrenal androgens, commonly accompanies cushing syndrome.
adrenogenital
the hormone that stimulates osteoblast activity, and thus prevents an increase in blood calcium levels, is _______.
calcitonin
PTH is secreted in response to low levels of the mineral _______.
calcium
increased heat production is called a _______ effect.
calorigenic
thyroid hormone accelerates the breakdown of what?
carbohydrates, fats, proteins
growth hormone is produced throughout your lifetime. during which period are its effects most evident?
childhood
after synthesis in the skin, ________ is converted in the liver and kidneys into the hormone calcitriol.
cholecalciferol
enteroendocrine cells of the small intestine produce which hormone in response to fat in the chyme arriving from the stomach?
cholecystokinin
steroid hormones are derived. from _______.
cholesterol
the general adaptation syndrome uses which horrmones?
epinephrine and cortisol
after a severe hemorrhage, one would expect levels of which hormone to be elevated?
erythropoietin
when they secrete eggs and sperm, the gonads are considered what type of glands?
exocrine
true or false: bound hormones can readily leave a blood capillary and get to a target cell.
false
true or false: organs can have only endocrine or exocrine functions, not both.
false
true or false: the inner core of the adrenal gland is called the adrenal cortex
false
true or false: control of pituitary secretions is limited to feedback from target organs.
false why? bc pituitary secretions are also controlled by other brain centers and the hypothalamus
true or false: hormones always function independently of other hormones.
false why? bc the interactive effects of hormones include antagonistic, synergistic, and permissive interactions.
true or false: the stage of resistance of the general adaptation syndrome can rapidly lead to death.
false. the stage of exhaustion can rapidly progress to death.
Cells called spongiocytes are found within the zona ______ of the adrenal cortex.
fasciculata
growth hormone stimulates the release of what into the blood?
fatty acids and glycerol
the hormone called _______ stimulating hormone stimulates the secretion of ovarian sex hormones and the development of the ovarian follicles.
follicle
steroid hormones enter the target cell nucleus and act directly on the _______, changing target cell physiology by either activating or inhibiting transcription.
genes
which hormone is secreted by the stomach and acts on a center in the hypothalamus to produce the sensation of hunger?
ghrelin
what is the physiological basis for gigantism and dwarfism?
gigantism results from hypersecretion of GH, while dwarfism results. from hyposecretion of GH.
pancreatic alpha cells secrete the hormone _______ when serum glucose levels drop.
glucagon
which pancreatic hormone stimulates gluconeogenesis, glycogenolysis, and the release of glucose into circulation in response to decreased blood glucose?
glucagon
growth hormone stimulates the synthesis of what by the liver?
glucose
the term that refers to the blood glucose concentration is _______.
glycemia
which would you expect to see in a urinalysis of an untreated diabetic?
glycosuria, ketonuria
what is an increase in the size of the thyroid gland that results from excessive TSH called?
goiter
the anterior pituitary hormones follicle stimulating hormone and luteinizing hormone are classified as _______ hormones because they target and stimulate the release of hormones from the gonads.
gonadotropic
unlike the other pituitary hormones, which hormone has widespread effects on the body?
growth hormone (gh)
which pituitary hormone stimulates ovulation?
luteinizing hormone (LH)
which pituitary hormone stimulates ovulation?
luteinizing hormone (lh)
The inner core of the adrenal gland is called the adrenal ________.
medulla
gonadotropin secretion might be suppressed by which hormone?
melatonin
the pineal gland synthesizes which hormone?
melatonin
excess hormone may bind to receptor sites and do which of the following?
mimic their effects
the pancreas is located retroperitoneally and _______.
posterior to the stomach
the pancreas is located retroperitoneally and _______.
posterior to the stomach.
in the ovary, the corpus luteum produces which hormone?
progesterone
what is the most diverse group of eicosanoids?
prostaglandins
growth hormone suppresses protein breakdown and enhances which of the following?
protein synthesis
when cells cannot absorb glucose, as occurs in diabetes mellitus, they metabolize which of the following?
protein, fat
growth hormone stimulates the liver and other tissues to produce growth stimulates called insulin-like growth factors which are also called what?
somatomedins
the pancreatic hormone that inhibits the secretion of stomach acid is _______.
somatostatin
match each pituitary cell type with the hormone that it produces.
somatotropes ---> growth hormone lactotropes ---> prolactin corticotropes ---> adrenocorticotropic hormone gonadotropes ---> follicle stimulating hormone
which stage of stress response occurs after fat reserves have been depleted and the breakdown of protein begins?
stage of exhaustion
if a stressful situation is not resolved before glycogen is gone, the body enters which phase of GAS during which the priority is to provide alternate fuels for metabolism?
stage of resistance
what is a situation that upsets homeostasis and threatens one's physical and emotional well-being?
stress
what does thyroid hormone refer to?
t3 and t4
organs that have receptors for a specific hormone are referred to as which of the following?
target organs
which endocrine organ is located in the scrotum?
testis
which hormone directly stimulates development of the male reproductive system, secondary sexual characteristics, and sustains sperm production and the sex drive throughout adult life?
testosterone
which two hormones are synergists?
testosterone and FSH
among their many functions, norepinephrinie and epinephrine also play an important role in which of the following?
the alarm reaction of the stress response.
what is glycemia?
the blood glucose concentration
what sone difference between the endocrine and the nervous system?
the nervous system is more targeted in its response.
true or false: the function of melatonin is uncertain, though it seems to regulate the gonads.
true
which condition requires insulin injections or insulin infusions to maintain blood glucose?
type 1 diabetes mellitus
which condition is characterized by insulin resistance?
type 2 diabetes mellitus
which endocrine condition can often be managed through a weight-loss program (diet and exercise) supplemented with medication?
type 2 diabetes mellitus
which amino acid is thyroid hormone composed of?
tyrosine
what is the thin layer of the adrenal cortex just beneath the capsule that produces mineralocorticoids?
zona glomerulosa
what is the innermost layer of the adrenal cortex?
zona reticularis
which pancreatic cells secrete insulin?
beta cells
to get from an endocrine gland to its target cell, a hormone must travel through what?
blood
because endocrine secretions are carried in the blood, endocrine glands have a high density of which of the following?
blood capillaries
the stress response is mediated by what system(s)?
both the endocrine system and the sympathetic nervous system.
which glands secrete their product into interstitial fluid or blood?
endocrine
the _________ system has widespread effects while the _________ innervates one organ at a time.
endocrine, nervous
which area of the brain monitors conditions within and outside of the body?
hypothalamus
which brain area closely regulates pituitary function?
hypothalamus
where is the thymus located?
in the mediastinum
where do steroid hormones bind with a cell's receptor?
in the nucleus
where are parrafollicular cells found?
in the thyroid gland
what is the function of of antidiuretic hormone (adh)?
increases water retention by the kidneys
where is the pineal gland?
inferior to the posterior portion of the corpus callosum
which hormone suppresses FHS secretion by negative feedback?
inhibin
during and immediately following carbohydrate rich meal, the beta cells of the pancreas secrete the hormone _______.
insulin
the hormone that antagonizes the effects of glucagon by surpassing the breakdown of glycogen is _______
insulin
the pancreas synthesizes _______.
insulin
which of the following is a hypoglycemic hormone?
insulin
located between the seminiferous tubules of the testis are clusters of _______ endocrine cells that secrete testosterone.
interstitial
endocrine secretions interact with their target cells and lead to which of the following?
intracellular changes
the two lobes of the thyroid gland are joined by a narrow bridge of tissue called the _______.
isthmus
how does the cortisol function in the stage of resistance?
it promotes the breakdown of fat and protein
adipose tissue secretes the hormone _______ which has effects on the appetite center of the hypothalamus.
leptin
the nervous system is similar to the endocrine system in that both work through chemical messengers to affect physiological responses. however, the nervous system has a _______ response.
less persistent
because histamine diffuses to and interacts only with nearby tissues it is classified as a _______ signal.
paracrine
what are chemical messengers that diffuse through tissue fluid and affect only nearby cells called?
paracrines
the thyroid gland contains areas of c (clear) cells, also called _______ cells, between the follicles.
parafollicular
which cells of the thyroid gland produce calcitonin?
parafollicular
the ovoid glands partially embedded in the posterior surface of the thyroid are the _______ glands.
parathyroid
when one hormone enhances a target organ's response to a second hormone, this is called what?
permissive
which gland is thought to play a role in establishing 24-hour circadian rhythms?
pineal gland
hypothalamic releasing hormones stimulate which gland to release hormones?
pituitary gland
the adenohypophysis and the neurohypophysis form which organ?
pituitary gland
which endocrine gland is housed in the sella turcica of the sphenoid bone?
pituitary gland
which endocrine organ is encircled in the figure?
pituitary gland
estrogen from what organ inhibits the mammary glands from responding to prolactin until birth?
placenta
in addition to the ovary, what organ secretes progesterone and estrogen?
placenta
the thyroid gland is composed of sacs called _______ which are filled with a protein-rich colloid.
thyroid follicles
the thyroid gland is composed of sacs called _______ which are filled with protein-rich colloid.
thyroid follicles
thyroid stimulating hormone stimulates growth and function of which of the following?
thyroid gland
what is the largest endocrine gland in an adult?
thyroid gland
what is the function of a hyperglycemic hormone?
to increase blood glucose levels
what is the function of oxytocin?
to stimulate contraction of the smooth muscle of the uterus
what is the function of growth hormone?
to stimulate mitosis and cell differentiation
through which of the following can cell-to-cell communication can be accomplished? select all that apply:
*hormones *gap junctions *paracrines *neurotransmitters
which secrete steroid hormones?
*ovary *testes *adrenal cortex
which are peptide hormones?
*oxytocin *insulin *follicle-stimulating hormone
what are the three types of interactive effects hormones can have?
*permissive *synergistic *antagonistic
arachidonic acid is converted by cyclooxygenase to which three eicosanoids?
*prostaglandins *prostacyclin *thromboxanes
match each pituitary cell type with the hormone that it produces.
*somatotropes: growth hormone *lactotropes: prolactin *corticotropes: adrenocorticotropic hormone *gonadotropes: follicle-stimulating hormone
what are the functions of the testosterone?
*to develop the male physique *to develop the male reproductive system *to fuel the sex drive
which are functions of transport proteins? select all that apply.
*to protect hormones from filtering by kidneys *to protect hormones from enzyme breakdown
what are the target cells of insulin?
*adipose *liver *skeletal muscle
which substances are secreted by pancreatic islet cells?
*glucagon *insulin *somatostatin
which hormones are produced by the liver?
*hepcidin *insulin-like growth factor *erythropoietin
which hormones are produced by the endocrine gland indicated in this picture?
(picture is of thymus) triiodothyronine (T3) and thyroxine (T4)
place the stages of the general adaptation syndrome in order.
1. alarm reaction 2. stage of resistance 3. stage of exhaustion
place the steps of a second-messenger system in the order in which they occur:
1. hormone receptor binding activates g-protein 2. g protein activates adenylate cyclase 3. adenylate cyclase produces cAMP. 4. cAMP activates protein kinases
what is the fate of most hormones?
They are degraded by the liver and kidneys.
which adrenal cortical hormone helps maintain blood pressure and blood volume?
aldosterone
peptide hormones are comprised of chains of what?
amino acids
after menopause, which hormones are converted to estrogen to make up for the non-functioning ovaries?
androgens
which adrenal cortical hormones stimulate somatic changes at puberty in both sexes?
androgens
where is the adrenal medulla?
at the core of the adrenal gland, superior to the kidney
which hormone is produced by the heart?
atrial natriuretic peptide (ANP)
_______ hypothyroidism is due to a thyroid hyposecretion from birth.
congenital
what is the middle portion of a newly synthesized peptide prohormone called?
connecting peptide
the region of the adrenal gland indicated by the red arrow in the figure is the adrenal _______.
cortex
Immunity is depressed by long-term exposure to the stress hormone ______.
cortisol
_______ is a potent glucocorticoid that stimulates fat and protein catabolism, gluconeogenesis, and the release of fatty acids into the blood.
cortisol
which hormones are classified as steroid hormones? select all that apply
cortisol, testosterone
which condition results from excessive cortisol secretion?
crushing syndrome
a condition defined as a disruption of carbohydrate, fat, and protein metabolism resulting from hyposecretion or inaction of insulin is ___ ___.
diabetes mellitus
a condition defined as a disruption. of carbohydrate, fat, and protein metabolism resulting from hyposecretion or inaction of insulin is _______.
diabetes mellitus
what is the most prevalent metabolic disease in the world?
diabetes mellitus
which are monoamines?
dopamine and norepinephrine
target cells can become less sensitive to a hormone by decreasing the number of receptors via which process?
down-regulation
hormone specificity:
each hormone binds to only one receptor
which defines hormone specificity?
each receptor binds to only one hormone.
what are the symptoms of myxedema?
edema, weight gain, and lethargy.
The rapid metabolism of fats that occurs in diabetes mellitus promotes an osmotic diuresis that, in turn, can result in ______, ______, and ______.
electrolyte imbalances, dehydration, ketoacidosis
where are the parathyroid glands located?
embedded in the thyroid gland
while both the endocrine and nervous systems are involved with communication, they differ in their mechanisms. what is one difference between hormones of the endocrine system and neurotransmitters of the nervous system?
hormones are released into interstitial fluids while neurotransmitters are released into the synaptic cleft.
steroid hormones and thyroid hormone are which of the following?
hydrophobic
the condition of elevated blood glucose is called ________.
hyperglycemia
which condition is characterized by an increased level of calcium in the blood and soft, deformed, fragile bones?
hyperparathyroidism
which condition is characterized by a rapid decline in blood calcium levels that can lead to a fetal tetany?
hypoparathyroidism
what term means inadequate hormone release?
hyposecretion
many of the functions of which organ are carried out by way of the pituitary gland, which is closely associated with it both anatomically and physiologically?
hypothalamus
where are the paraventricular nucleus and supraoptic nucleus located?
hypothalamus
after consuming a carbohydrate rich meal, insulin is released by the pancreas to lower serum glucose levels. when serum glucose levels have returned to normal the secretion of insulin is inhibited. this is an example of which feedback mechanism?
negative feedback inhibition
stimulation of stretch receptors in the heart and arteries inhibits the release of adh from the posterior pituitary. this is an example of what type of reflex?
neuroendocrine
what are neurons that release their secretions into the bloodstream called?
neuroendocrine cells
some compounds serve as both neurotransmitters in the nervous system and hormones in the endocrine system. what is one example of such a compound?
norepinephrine
what are monoamines?
norepinephrine, dopamine, serotonin
which catecholamines are secreted by the adrenal medulla?
norepinephrine, epinephrine, dopamine
peptides and catecholamines are hydrophilic and cannot penetrate a target cell. they therefore bind to receptors where?
on the cell surface
which bone hormone increases the pancreatic output of insulin?
osteocalcin
the ______ does not provide fetal nutrition or remove wastes.
ovary
which secrete steroid hormones?
ovary, testes, adrenal cortex
what are the two hormones stored and released by the posterior pituitary gland?
oxytocin (ot) and antidiuretic hormone (adh)
which endocrine gland also acts as an exocrine gland?
pancreas
the kidney secretes the enzyme _______ which acts to convert angiotensinogen to angiotensin I.
renin
where are the ovaries located?
retroperitoneal in the pelvic cavity
receptor molecules have hit _______ when they are all occupied by hormone molecules.
saturation
endocrinology involves the study of cells that do which of the following?
secrete hormones
the hormone melatonin is produced from what neurotransmitter?
serotonin
which adrenal cortical hormones have various developmental and reproductive functions?
sex steroids
one hormone molecule can stimulate the synthesis of hundreds of other enzyme molecules. what is this known as?
signal amplification
hormones bound to transport proteins have a(n) _______ metabolic clearance rate than those free in the blood.
slower
within the kidney, growth hormone promotes the retention of what?
sodium, chloride, and potassium
insulin and glucagon exert opposing effects and thus have what type of relationship?
they are antagonists
how do most steroids differ from one another?
they differ in the functional groups attached to their backbone structure.
which describes neuroendocrine cells?
they release their secretions into the bloodstream.
what do thromboxanes do?
they stimulate vasoconstriction and clotting.
what is acromegaly characterized by?
thickening of the bones and soft tissues
which are produced by blood platelets and stimulate vasoconstriction and clotting?
thromboxanes
which hormones are secreted by thymus gland? select all that apply.
thymopoitein and thymulin
which endocrine gland secretes several hormones that stimulate lymphatic organs and T cell activity?
thymus
which endocrine gland serves as the site of T lymphocyte maturation?
thymus
which endocrine organ is indicated in the figure?
thymus
which gland is located in the mediastinum superior to the heart?
thymus
the pituitary hormone that stimulates the secretion of thyroid hormone is _______ stimulating hormone
thyroid
antidiuretic hormone (ADH) is also called arginine _______ because it can cause vasoconstriction at very high levels.
vasopressin
antidiuretic hormone is also called arginine _______ because it can cause vasoconstriction at very high levels
vasopressin
