Egestion is also known as the defecation and it is the process that causes the removal of the undigested food material left behind after the completion of the absorption process. In this process the faecal matter that is stored in the last part of the large intestine passes through the rectum and then it leaves from the body through the anus.
All living organisms need nutrients and oxygen for survival. In this process, the waste products are discharged which can no longer stay in the body system. Based on the nature of discharged material these substances can be classified into different materials. The material that is digested by the egestion is an undigested matter that is leftover by the process of digestion.
Process of Egestion
Egestion only occurs in human beings and animals. After the ingestion of food, it is being digested and the nutrients are absorbed through the gastrointestinal tract. After this, the remaining waste products must have to be removed from the body. In the unicellular organisms, the egestion takes place through the cell membrane and in the multicellular organisms, it takes place through the anus.
Unavoidably, animals and human beings may take the bulk of food and then their body is incapable to use it. The unicellular organisms make the food vacuole and eventually, the vacuoles are fused with the cell membranes, and then they are ruptured thus releasing the undigested food to the outer environment. While in the multicellular organisms the undigested substances are passed to the large intestine or the colon, where the water and the important ions are reabsorbed and the solid material is expelled through the anus.
Simply the egestion is the passing out of the undigested food from the end of the large intestine. It is most likely the plant fiber and the cellulose material which is ingested by the days ago, but has not been digested and not even absorbed so it came out from the other end. The presence of the bile pigments causes the color of the faeces to the brown or dark brown.
Some Important Points About Egestion
In the large intestine, the excess water is absorbed back to the body and only undigested food is left there. This undigested food is stored in the rectum that is the lower part of the large intestine. Then it comes out of the rectum through the anus as faeces. Many bacteria are present in the digestive system which are important for the process of digestion and egestion. These bacteria help to digest the substances, which otherwise the human body is not able to do.