Question

Digestion and Absorption)

Answer 1

Digestion and absorption is one of the most important process in our body for the human being to survive.

It is one of the process that takes place in the body in our digestive system.

Our digestive system comprises of major and accessory parts.

The major part of digestive system consists of:

- mouth

- salivary gland

- pharynx

- oesophagus

- stomach

- small intestine

- large intestine

- rectum

And the accessory parts consists of:

- liver

- gall bladder

- pancreas

The main function of digestive system is digestion and absorption. Digestion is the breaking down of the complex food into simple particles or molecules and then it is absorbed into our body.

The digestion process is the process of interaction of the food with the juices produced by the digestive system and the digestive hormones. It starts from the mouth and continues through its travelling down. It is the process in which all the complex nutrients such as far, carbohydrate, protein, vitamins, minerals etc are broken down into simple form in order to facilitate in easy absorption of these nutrients by our body system.

The digestion starts in the mouth as soon as the food is taken, the food is broken down into smaller pieces by the process of chewing and the saliva produced by the salivary gland mixes with the food and starts the process of breaking down. Next the food enters into the pharynx and travels through the oesophagus. Oesophagus is a tube made up of muscles which connects the pharynx to the stomach. The food travels through the oesophagus by the process of peristaltic movement. At the end of the oesophagus from where the stomach starts there is a zone of high pressure as it is guarded by a valve or sphincter which stops the food from backflow. Now the food enters into the stomach which is a bag like structure made up of very strong muscular wall. It is known for carrying the food and also has other functions like mixing and grinding. Some powerful acid as well as enzymes are secreted by the stomach in order to improve the breakdown of the food. Now the food turns into liquid or semi solid form while leaving the stomach. The next area is the small intestine. The small intestine has three different parts i.e, duodenum, jejunum and ileum. Small intestine is a long tube measuring more than 20feet long is present into the body in the coiled form. The process of breaking down of the food is continued in the small intestine by using various enzymes secreted by pancreas and liver. Bile helps in the digestion of the fat and elimination of the waste products from the blood. In this organ also the food moves forward with the help of peristaltic movement and mixes up with the digestive secretions while moving. The digestion process ends in the duodenum whereas the absorption process starts in the jejunum and ileum.

Pancreas breaks down the complex protein, fat and carbohydrate into simpler forms which are easy to absorb. Liver has mainly two functions which are to secrete bile and to purify the blood in the small intestine after the absorption of food. Gall bladder is present under the liver and is responsible for storing the bile.