Intracellular digestion and extra cellular digestion

Intracellular digestion

           Digestion is the process by which complex molecules of food are broken down into simple molecules. This process is more or less the same whether the animal is a single called Amoeba or a complex multicellular organism like man.

              There are two types of digestion in animals. they are 1) Intracellular digestion and 2) Extra cellular digestion.

1. Intracellular digestion

            In unicellular organisms like Amoeba and paramecium, the food is ingested by means of pseudopodia and digested in food vacuoles by enzymes. The digested food is absorbed by diffusion. This type of digestion is known as intracellular digestion.

2. Extracellular digestion 

             In the higher organisms, There are special organs for the digestion of food. The food in these organisms passes through the alimentary canal. Here several digestion enzymes are secreted to break the complex food materials into simpler substances. In this type, digestion occurs not within the cell, but inside the cavities of the alimentary canal. This is called extra cellular digestion.