Question

Explain the digestive system of Cockroach with the help of a labelled sketch.

Answer 1

The digestive system consists of an alimentary canal and digestive glands. The alimentary canal of cockroaches is divided into the foregut, midgut and hindgut. The mouth opens into a short tubular pharynx, leading to a narrow tubular passage, the oesophagus, which opens into a sac-like crop used for storing food. The crop is followed by a gizzard or proventriculus. Gizzard consists of six chitinous plates called teeth which help in grinding food. The entire foregut is lined by cuticles. A ring of six to eight blind tubular structures called hepatic or gastric cancer is present at the junction of the foregut and midgut which secrete digestive juice. At the junction of midgut and hindgut is present another ring of yellow-coloured thin filamentous malpighian tubules which help in the removal of excretory products from the haemolymph. The hindgut is broader than the midgut and is differentiated into the ileum, colon and rectum. The rectum opens out through the anus.

            Alimentary canal of cockroach