Small Intestine


 
 
Concept Explanation
 

Small Intestine

Small Intestine: It is highly coiled long tube with length of about 7.5 metre. The small intestine is a narrow tube which receives secretions from the liver and pancreas. The wall of small intestine also secretes digestive juices. The complete digestion of food takes place inside the small intestine and the food components are also absorbed here. It cosists of three parts duodenum, jejunum and ileum. In duodenum, the liver and pancreas pour their secretions. Liver secretes the bile juice and pancreas secretes the pancreatic juice. The bile juice contains the bile which carries out emulsification of fats. In this process, the fat is converted into tiny droplets.The pancreatic juice contain several enzymes.The enzymes of pancreatic juice break down starch into simple sugars and proteins into amino acids.

Absorption in the Small Intestine:The blood vessels in the walls of the intestine absorb the digested substances to produce energy for growth and development of animals. The inner walls of small intestine have thousands of finger like outgrowths called ‘villi.’ These villi help in increasing the surface area of small intestine for the absorption of digested food. Villi possess a network of thin and small blood vessels to its surface. These blood vessels absorb the digested food materials and transport it to the different organs of the body where these are used to build repair the body and to provide energy.

The glucose breaks down into carbon dioxide and water and release huge amount of energy with the help of oxygen inside the cell. Fatty acid and glycerol help in building the component of cells and form fats which is stored in the body as food reserve while amino acid is used in growth and repair of the body. The undigested food material is not absorbed by the small intestine and it passes from here to the large intestine.

                         

Sample Questions
(More Questions for each concept available in Login)
Question : 1

Which of the following are correct ?

(a) Small intestine is about 6 metre in length and 2.5 cm in thickness.

(b) Duodenum is the first part of small intestine .

(c) In Small intestine the inside to outside layers are mucosa, submucosa,muscularis and serosa.

Right Option : D
View Explanation
Explanation
Question : 2

__________________ secretes the bile juice.

Right Option : A
View Explanation
Explanation
Question : 3

Digestion of food does not occur in the _______________

Right Option : D
View Explanation
Explanation
 
 
Related Videos
Language - English
Language - English


Students / Parents Reviews [20]