Question

The ingrowth of exoskeleton in the head of cockroach is called
a. Notum
b. Apodemes
c. Pleura
d. tentorium

Answer 1

Notum is the dorsal part of the insect’s thoracic segment or the dorsal segment of the body of insects. Apodeme is the infected part of the muscle which attaches to the exoskeleton and acts as the tendons. Pleura is the lateral sclerite of the thoracic segment present in the insects. Tentorium is the part of the internal skeleton which provides the strength to the head capsule and also provides the space for muscle attachment.

Complete answer:
The correct answer to this question is the last option that is the (d) tentorium. As the tentorium is the part of the internal skeleton which provides the strength to the head capsule and also provides the space for muscle attachment. The tentorium is formed by the tube-like shaped inward extensions which are the part of the exoskeleton.
The maxillary, labia papillae, and mandibles are all visible. The main part which helps a lot to the exoskeleton for its growth is the tentorium. So the correct option for this question is the tentorium.
If we see the first option that is the notum, is the wrong answer for this question as because notum is the dorsal part of the insect’s thoracic segment or the dorsal segment of the body of insects, hence it is not the head in growth extension, it is the wrong answer.
The second option that is the apodemes is also the wrong answer because apodeme is the infected part of the muscle which attaches to the exoskeleton and acts as the tendons. So this option is also not the growth of exoskeleton, hence this is also the wrong answer. Pleura is also not the correct option.

Additional Information:
Tentorium is a term used to refer to the basic framework internal kind of support which is present in the head region of arthropods.
Tentorium is formed by the growth of the exoskeleton also called apophyses, which can fuse in various ways so that it provides a rigid kind of support to the muscles of the head region.

Note: Cockroaches have three segments in the body that are as follows, head, thorax, and abdomen. They have the long antennae which are used by them to take care of food and smell. These antennae are attached to the head portion of the cockroaches. When the skeleton is present on the outside it is called an exoskeleton. Their exoskeleton is made up of the substance called chitin. This makes it hard in appearance.