DIGESTION IN PLANARIANS

DIGESTIVE SYSTEM

In planarian mouth lines on the ventral side at the end of a short, thick walled, cylindrical pharynx. The pharynx can protrude out of sucking in food.

The cavity of the pharynx opens into the intestine which almost immediately divides into three branches, a central branch extending forwards, and two lateral branches extending backwards. Each branch further divides into a large number of small branches which end blindly. Thus a branching gastrovascular system is formed extending throughout the body and increasing the surface concerned with digestion, absorption and distribution.

 

FOOD

The food of a planarian mostly consists of dead animals but it can capture live aquatic organism also.

 

DIGESTION

In planarian the food is digested by extracellular as well as intracellular digestion. The digested food is transported by intestine and its branches which reach almost every part of the body. Undigested food particles are expelled out of the mouth.