Question

Mandibles of cockroach are
A. Short with grinding teeth
B. Long and pointed
C. Short without teeth
D. Long and coiled

Answer 1

The body of the cockroach is segmented and elongated. The cockroach is dark or reddish-brown in colour. On the ventrally positioned head, the mouth of the cockroach is present. The mouthparts assist in the biting and chewing of food. Sclerites are the calcareous plate in a thick and rough exoskeleton cockroach.

Complete answer: Sensory receptors found on the antennae and maxillary palps 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. Maxillae, prostheca of mandibles, and labium from where they are swallowed into the mouth force the chewed food into the pre-oral cavity. Mandibles are just a set of miniature cockroach structures, triangular, stiff, unjointed, chitinized, that are located on either side of the mouth. In front of the weaker maxillae, the mandibles lie and their lateral movements aid in biting and crushing the food. The mandible of the cockroach is well sclerotized (hardened), with the best sclerotization occurring in the teeth. It helps to properly grind the food. The inner margins of mandibles have structures like teeth. There are two styles of teeth on each mandible. Its teeth incising and teeth grinding. These teeth allow food to be chewed.
Hence with grinding teeth, cockroach mandibles are short.
So,' Short with grinding teeth' is the right answer, i.e., Option A.

Note: There are various mouthparts of the cockroach and the function of each part varies. The function of the mouthparts of cockroaches is the chewing and cutting of food, tasting of food, etc. The cockroach's body is divided into three sections, called the head, the thorax, and the abdomen. There are three pairs of jointed appendages in the cockroach and two pairs of wings.