EVERYDAY SCIENCE

Detailed explanation-1: -Cnidarians take in food through their mouths, which is then digested in the coelenteron. Nutrients are then passed to other areas of the body for use, and waste products are expelled either through the mouth or through surface cells via water circulation.

Detailed explanation-2: -Cnidarians digest their food using a primitive digestive system that contains no organs–they have a mouth (which also serves as the anus) and a gastrovascular cavity. The gastrovascular cavity is a special area of the animal’s body that provides a place for food to be digested using cellular digestion and enzymes.

Detailed explanation-3: -Cnidarians carry out extracellular digestion, where enzymes break down the food particles and cells lining the gastrovascular cavity absorb the nutrients. Cnidarians have an incomplete digestive system with only one opening; the gastrovascular cavity serves as both a mouth and an anus.

Detailed explanation-4: -The mouth opens into a flattened invagination known as the pharynx, which in turn opens into the gastrovascular cavity.

Detailed explanation-5: -Cnidarians have no well-defined separate respiratory, circulatory, or excretory organs; their tissues, composed of two cell layers, surround a cavity known as a coelenteron (gastrovascular cavity), which is the basic internal organ. Tentacles surrounding the mouth are used to capture and ingest food.