Class 11 NEET Biology Structural Organisation in Animals

(d) : Mouth part of cockroach contain two mandibles, which bears teeth. When both the mandibles work simultaneously in a horizontal plane, the food matter is cut and masticated into fine and smaller pieces. Gizzard is a part of alimentary canal. It bears six muscular folds which are covered by chitinous conical plates, the teeth, used for grinding the food.