the

structure of villi

in our body absorption of food mainly

takes place in the small intestine the

inner wall of the small intestine is

highly folded and has many small

projections called villi the structure

of the villi is specially adapted for

food absorption the villi are

finger-like and large in number these

features greatly increase the surface

area for absorption

moreover the epithelium of the villi is

only one cell thick this provides a very

short distance for diffusion of food

molecules into the blood the cell

membrane of the epithelial cells has a

large number of micro villi this further

increases the surface area for

absorption

each villus has a lymph vessel called

lacteal in the center the lacteal is

surrounded by a network of capillaries

these allow the absorbed food molecules

to be carried away rapidly therefore a

steep concentration gradient of food

molecules can be kept across the wall of

the small intestine to increase the rate

of diffusion of food molecules