OSU PSYCH 3313 CH 9/10/11 || A+ GUARANTEED.
Understand the steps in the general homeostasis pathway. correct answers stimulus -> receptor ->
control (hypothalamus) -> effector -> (negative feedback) -> receptor
Understand the difference between the parts of the homeostasis pathway that are attempting to
return the body to a biological set point vs the part of the pathway that is the negative feedback
loop that prevents overshoot. (In relation to thermoregulation, fluid regulation and nutrition
intake). correct answers thermoregulation- TRH and TSH released by hypothalamus/anterior
pituitary cause release of TH that goes and brings back body temp to set point. Once set point is
reached, these effects inhibit release of more TRH/TSH.
fluid regulation- once body reaches desired amount of fluid, these will signal baroreceptors and
osmoreceptors & will stop the effector pathway to prevent from overshoot.
nutrition intake- hungry -> eat, when full, high leptin levels, high insulin, and low ghrelin levels
reduce production of neuropeptide Y, don't feel hungry & stop eating
What changes occur in response to cold and hot environmental temperatures? correct answers
cold environment response- posterior hypothalamus is control region, blood vessels constrict and
muscles shiver
hot environment- preoptic area of hypothalamus responds, tells blood vessels to dilate and start
to sweat
What hormones are involved in thermoregulation? correct answers TRH- released by
hypothalamus onto anterior pituitary gland
TSH- released by anterior pituitary onto thyroid
TH- released by thyroid and targets specific organs to return to set point, negative feedback
inhibition of anterior pituitary and hypothalamus
, Understand how changes in osmolarity can result in cell shrinking or expanding correct answers
hypertonic solution: osmolarity is higher (greater concentration of solutes) in solution, fluid from
cells exits and cell shrinks
hypotonic solution: osmolarity is higher inside cell (greater concentration of solutes inside), fluid
from outside enters cells, cells expand
What changes would stimulate the sensation of thirst? correct answers hypovolemic thirst:
sensed by baroreceptors in heart and kidneys, volume of extracellular fluid (blood, CSF,
interstitial) decreases usually due to injury
osmotic thirst: sensed by osmoreceptors in brain, concentration of salts is high in extracellular
fluid -> cellular dehydration (hypertonic)
What role does antidiuretic hormones (ADH) have in the context of the homeostasis of fluid
levels in the body. correct answers ADH (vasopressin) aims to retain fluid levels when thirsty,
reduce production of urine
What is the role of ghrelin, leptin, insulin and neuropeptide Y, and endogenous opioids in regard
to hunger and satiety? correct answers ghrelin- hunger hormone, produced in stomach lining,
when high ghrelin, high appetite and high calorie food cravings. rise since last ate
leptin- made in adipose tissue, inhibits NPY, but when levels are low, stimulates NPY release and
appetite. fall since last ate
Insulin- made by pancreas, helps cells get glucose that bloodstream has absorbed, also inhibits
NPY and appetite, levels fall since eating
NPY- increases appetite, released by hypothalamus
Understand the steps in the general homeostasis pathway. correct answers stimulus -> receptor ->
control (hypothalamus) -> effector -> (negative feedback) -> receptor
Understand the difference between the parts of the homeostasis pathway that are attempting to
return the body to a biological set point vs the part of the pathway that is the negative feedback
loop that prevents overshoot. (In relation to thermoregulation, fluid regulation and nutrition
intake). correct answers thermoregulation- TRH and TSH released by hypothalamus/anterior
pituitary cause release of TH that goes and brings back body temp to set point. Once set point is
reached, these effects inhibit release of more TRH/TSH.
fluid regulation- once body reaches desired amount of fluid, these will signal baroreceptors and
osmoreceptors & will stop the effector pathway to prevent from overshoot.
nutrition intake- hungry -> eat, when full, high leptin levels, high insulin, and low ghrelin levels
reduce production of neuropeptide Y, don't feel hungry & stop eating
What changes occur in response to cold and hot environmental temperatures? correct answers
cold environment response- posterior hypothalamus is control region, blood vessels constrict and
muscles shiver
hot environment- preoptic area of hypothalamus responds, tells blood vessels to dilate and start
to sweat
What hormones are involved in thermoregulation? correct answers TRH- released by
hypothalamus onto anterior pituitary gland
TSH- released by anterior pituitary onto thyroid
TH- released by thyroid and targets specific organs to return to set point, negative feedback
inhibition of anterior pituitary and hypothalamus
, Understand how changes in osmolarity can result in cell shrinking or expanding correct answers
hypertonic solution: osmolarity is higher (greater concentration of solutes) in solution, fluid from
cells exits and cell shrinks
hypotonic solution: osmolarity is higher inside cell (greater concentration of solutes inside), fluid
from outside enters cells, cells expand
What changes would stimulate the sensation of thirst? correct answers hypovolemic thirst:
sensed by baroreceptors in heart and kidneys, volume of extracellular fluid (blood, CSF,
interstitial) decreases usually due to injury
osmotic thirst: sensed by osmoreceptors in brain, concentration of salts is high in extracellular
fluid -> cellular dehydration (hypertonic)
What role does antidiuretic hormones (ADH) have in the context of the homeostasis of fluid
levels in the body. correct answers ADH (vasopressin) aims to retain fluid levels when thirsty,
reduce production of urine
What is the role of ghrelin, leptin, insulin and neuropeptide Y, and endogenous opioids in regard
to hunger and satiety? correct answers ghrelin- hunger hormone, produced in stomach lining,
when high ghrelin, high appetite and high calorie food cravings. rise since last ate
leptin- made in adipose tissue, inhibits NPY, but when levels are low, stimulates NPY release and
appetite. fall since last ate
Insulin- made by pancreas, helps cells get glucose that bloodstream has absorbed, also inhibits
NPY and appetite, levels fall since eating
NPY- increases appetite, released by hypothalamus
