Enzymes which break down macromolecules into smaller units are called digestive enzymes. The larger molecules are broken down into smaller particles so that they can be easily absorbed by the body.
These enzymes are found in the digestive system of the body of animals and human beings. For carnivorous plants, they are found in the traps. Digestive enzymes help in the digestion of food. Apart from the digestive tract, digestive enzymes are heavily found in the saliva which is a secretion of the salivary glands and it plays a major part in the process of digestion.
They are also found in the stomach where the enzymes are secreted by the cells in the stomach lining. Pancreatic juice and intestinal secretions also contain digestive enzymes.
Our body is built in such a way that we eat food and the nutrients from the food are absorbed by the body which nourishes and strengthens us. But, our body is not capable of absorbing the nutrients directly from the food.
These come in the role of digestive enzymes. The enzymes break down the food into smaller units which the body can absorb, thus facilitating digestion. Thus, digestive enzymes are very important for the well-being of the body.
Digestive enzymes can be classified on the basis of their target substrates. The main digestive enzymes along with their substrates are as follows:
- Protease and peptidases- They split proteins into amino acids and small peptides
- Amylase- Carbohydrates like starch and sugar are split by Amylase into glucose
- Lipase- Lipase splits fat into three kinds of fatty acids and glycerol molecule
- Nuclease- Nucleotides and nucleic acids are split by nucleases
We eat our food through the mouth. The complex food particles need to be broken down into simpler molecules which are soluble and are easily absorbed. Therefore, digestive enzymes which are secreted by the salivary glands and the oral cavity break down the food into simpler units in the mouth.
The stomach secretes enzymes known as gastric enzymes. They help in breaking down the food into smaller particles which can be easily digested and absorbed by the bloodstream.
The pancreas is a gland which is both endocrine and exocrine. It produces hormones which are released directly into the circulatory system. It has many functions like controlling the glucose metabolism and secretion of digestive enzymes.
Apart from these, the small intestine also secretes digestive enzymes. Digestive enzymes are very important as they help in breaking down the food into smaller particles so that the nutrients can be easily extracted from them. Thus, digestive enzymes play a key role in maintaining and regulating the normal functions of the body.