homeostasis Flashcards
which factors control homeostasis
- blood ph
-blood glucose concentration
-temperature
-water potential of the blood
why does the blood glucose have to be stable
- provides sufficient substrate for respiration to release energy for metabolic processes in the body
why does water conc have to be maintained
- so excess water doesn’t enter or leave cells by osmosis causing cells to burst or dehydrate
what is the control system used in homeostasis
negative feedback that restores systems to their original level
why is the liver so important
- maintains the blood glucose concentration
-converts excess glucose to glycogen as storage
what detects the rise or fall of bgc , then what happens once so
the pancreas (beta cells ) ]
-secretes insulin into the bloodstream
what does insulin do when its been secreted
-binds to specific receptors on the surface of target cells of the liver and muscles
what does insulin do to the permeability of large cells to glucose
-increases by stimulating more Chanel proteins to open in the membrane
-which allow glucose to enter by diffusion , reducing blood conc
describe the connection between insulin and. enzymes when blood glucose is too high
- activates enzymes in the liver that convert glucose into glycogen (GLYCOGENESIS)
what is glycogenesis
when insulin causes the enzyme in the liver to convert glucose to glycogen
what hormone is secreted when blood glucose levels is too low
-glucagon
what does glucagon do when its secreted
attaches to specific receptors on target cells of the liver and activates enzymes that hydrolyse glycogen to glucose
what is glycogenolysis
when glycogen when bound to receptors on large cells of the liver, activate enzymes that hydrolyse glycogen to glucose , increasing blood glucose
whats gluconeogenesis
- glucagon activates enzymes that convert glycerol and amino acids into glucose .
