Question

Valves of Kerckring occur in:

Answer 1

Hint: These are a part of the alimentary canal of mammals. The alimentary canal and the associated glands form the Digestive system. The alimentary canal is designed in such a way that the food passes through it, gets digested and required nutrients are absorbed. The process of breaking food material to smaller ones to get absorbed is called digestion.

Complete Answer:
To Know the presence, structure and function of Kerckring valves, we need an overview of the alimentary canal.
Alimentary canal is between the mouth and the anus. The parts in the order-
Mouth-> Pharynx-> oesophagus-> stomach-> small intestine-> large intestine-> anus.
Small intestine:
Small intestine consists of duodenum, jejunum and ileum in the order of presence followed by the large intestine.
The alimentary canal consists of a wall or lining made up of mucosa, sub mucosa, muscularis externa and serosa. The mucosa surrounds the lumen. The mucosa of the small intestine will form some folds like fingers called villi. And the cells of villi at the outer layer produce more folds like brush called microvilli.
The circular folds of mucosa that project into the lumen of the small intestine are called Valves of Kerckring or plicae circulares. They are large valvular projections. They are mostly found in high numbers in jejunum and comparatively low in duodenum and ileum.
They are made for increased absorption of digested food. They also slow down the passage of food through the alimentary canal so as to make the digestion process easier and absorb more.

Note:
Kerckring valves are the foldings of mucous membranes of the intestine. The microvilli of the intestine absorb the nutrients, vitamins, minerals from the digested food that passes through the alimentary canal. The valves of Kerckring are also known as the valves of Kerckring.