Physiology: lipid digestion 2 Flashcards
what is responsible for triacylglycerol(TAG) digestion in the duodenum
pancreatic lipase
what cells are pancreatic lipases secreted from and in response to what
acinar cells of pancreas in response to CCK
what is required for full pancreatic lipase activity (5)
colipase co-factor, alkaline pH, Ca, bile salts and FAs
what does TAG digestion by pancreatic lipases produce
2-monoacylglycerol + free FAs
describe how bile salts enter the duodenum and in response to what
in bile from gall bladder in response to CCK
describe the role of bile salts in lipid digestion
act as detergents to help emulsify large lipid droplets to small lipid droplets
what does failure to secrete bile salts result in
lipid malabsorption and secondary vitamin deficiency
describe the action of bile salts
they increase the SA for attack by pancreatic lipases, but block access of enzyme to TAGs
how is the problem in bile salt digestion of TAGs solved
by colipase binding to bile salts and lipase, allowing access of lipase to TAGs
what is colipase secreted as and by what
secreted as inactive procolipase, with lipase by pancreas
how is procolipase activated
by trypsin
what is the final products of lipid digestion
mixed micelles
what ways are lipids absorbed (3)
as free FAs and monoacylgycerols
through chylomicron formation
by cholesterol absorption
