Digestive System Disorders and Health

A heterocrine gland (also known as a mixed gland) performs both exocrine and endocrine functions. The pancreas secretes digestive enzymes into the duodenum (exocrine) and hormones like insulin and glucagon into the blood (endocrine).

After digestion of complex food into the simple soluble form, the nutrients are absorbed by the small intestine with help of finger-like projection (villi) in the wall of the intestine. The wall of intention is surrounded by the blood vessels which possess assimilation of food. Assimilation is the process of transfer of soluble food from the intestine to different parts of the body through blood.

Vitamins are organic substances that help our bodies to function properly. Being a general source of energy supply these are crucial for the activities carried out by the cells and organs as well as the functioning of the body's immune systems. The human body goes through the process of bio-assimilation, which is actually the combination of two processes that help supply the cells with nutrients. The absorption of vitamins like minerals takes place in the gastrointestinal tract where it is broken down by enzymes and through the physical process of mastication. There is no chemical alteration of the substance. 

1. Assimilation means the absorption and digestion of food or nutrients by the body or any biological system. 
2. Assimilation of fats results in the formation of the end products of digestion of fats ie fatty acids and glycerols.
3. These are absorbed and taken into the lacteal and later the lymphatic system and then they are transferred to the liver. 
4. Fatty acid and glycerol can be used to form fats which are stored in the body’s fat deposits e.g. under the skin in the adipose tissue. Hence, the fatty acid and glycerol are transported from intestine mainly through the lymphatic system.

Food is first taken in from the mouth that is ingested. The food is converted to simple form i.e digestion and then it is absorbed by blood i.e absorption. The nutrients in the blood are taken to the cell for metabolic action i.e assimilation and then undigested food is thrown out of the body through anus that is egestion.