Absorption Of The Products Of Digestions Flashcards
What are the walls of the ileum like?
They have thin walls which are lined with epithelial cells on the other side of which is a rich network of blood capillaries.
Does the ileum have villi?
Yes
What do the villi do?
It increases the surface area of the ileum and therefore accelerate the rate of absorption.
Where are the villi situated?
At the interface between the lumen of the intestines and the blood and other tissues inside the body.
What is the lumen?
This is a cavity inside the tubular structure
Do the villi increase?
Increase the surface area for diffusion.
What reduces the distance over which diffusion takes place?
They are very thin-walled.
What enables the villi to move?
The muscle.
Why is the muscle of the villi useful?
It helps maintain diffusion gradients because their movement mixes the contents of the ileum.
Why is it beneficial that the villi are well supplied with blood vessels?
This is because blood can then carry away absorbed molecules which maintains a diffusion gradient.
What did the epithelial cells lining the villi possess?
Microvilli
What do the microvilli do?
They further increase the surface area for absorption.
How are amino acids and monosaccharides absorbed?
By diffusion and co-transport.
How are micelles absorbed?
Micelles come into contact with the epithelial cells lining the villi, causing them to break down and release monoglycerides and fatty acids.
How are monoglycerides and fatty acids absorbed?
They transported to the endoplasmic reticulum where they are recombined to form triglycerides.
