homeostasis Flashcards
what is the homeostasis
keeping constant conditions in the tissue fluid around the cells is called homeostasis
what is a negative feedback
a change sets off a response that cancels out the change
the importance of keeping body at a constant temperature
enzymes work best at their optimum temperature
cell membranes become more fragile as temperature rises
what are endotherms
animals can maintain a constant body temperature by generating heat inernaly
what happens if the environmental temperature increases
the detector detects the stimulus
integrator in vain
corrective mechanisms attempt to increases heat loss
body temperature back to normal
what happens in the skin structure when the environment temperature is too cold
sweat is not secreted
up straight hair to trap warm air insulates the skin
vasoconstriction- arterioles are supplied with less blood, the artery remains narrow( further from skin)
shivering- muscles contract and relax rapidly generates heat
what happens in the skin structure when the environmental temperature is too hot
sweat evaporates from the skin, take away heat
hairs lie flat, trap less air
vasodilation- more blood is brought, the vessel (arteriole) gets wider( closer to the surface) so more blood can lose heat.
which hormones control glucose concentration
insulin and glucagon
when is insulin secreted
when glucose concentration is too high, converts glucose to glycogen
when is glucagon secreted
when glucose concentration is too low, converts glycogen to glucose
where are insulin and glucagon secreted
pancreas
what is type 1 diabetes
usually, the result of the pancreas failing to produce enough insulin.
systoms: excessive thirst, hunger. sweet smelly breath.
long term: hardening arteries, heart diseases
treatment for type 1 diabetes
injection of insulin
what is hormone
a chemical substance produced by a gland, carried by the blood, which alters the activity of one or more specific target organs. and destroyed by the liver.
