Question

Organ of mastication of cockroach is
A. Mandibles
B. Maxilla
C. Labium
D. Labrum

Answer 1

Hint: Mandibles, maxilla, labium, labrum all are parts of a cockroach’s mouth. Mastication is usually performed by a pair of short, triangular, hard, unjointed structures present on either side of the mouth.

Complete answer: The mandibles are horizontal rigid chitin-made structures that are hinged to the cockroach skull. These move to grind and chew the food into smaller bits in a horizontal way and are often called the cockroach's primary jaws. Mandibles are fitted with a teeth-like structure and are used to chew food that enables fast digestion. Particular muscles re-associated with the mandibles help to move them in a horizontal plane to cut and chew the food particles introduced by the first maxillae between the mandibles. Sensory receptors found on the antennae and maxillary pals sense the presence of food in a cockroach. The maxillae pick up and hold food for chewing to the mandibles. The teeth of the mandibles bite and chew the food during the act of mastication. The labrum and labium behave like lips at the time of mastication to prevent the loss of food from the mandibles.
So, the correct answer is option A.

Note: Cockroaches belong to the order Blattodea. It is characterized by a flattened oval body, long thread-like antennae, and a shining black or brown leathery integument. Male cockroaches usually have two pairs of wings, whereas females, in some species, are wingless or have vestigial wings. Females lay eggs in a case called ootheca.