Question

In the mouthparts of cockroach the galea and lacinia form parts of the
A. Mandibles
B. Maxillae
C. Labium
D. Labrum

Answer 1

Hint: The appendages of the 5th segment consists of a pair of maxillae, which is also called as side lips. The galea functions like a cover and the lacinia are used for chewing food. The basal piece of the maxilla is known as cardo and the last piece carries 3-4 segmented palp that carries chemoreceptors.

Complete answer: Cockroach is the member of the phylum Arthropoda, class Insecta, order Blattodea, this order also includes termites. Mouthparts of this insect include three appendages, a paired mandibles, a paired maxillae, and an unpaired labium as well as additional head structures; the labrum and the hypopharynx. Galea and lacinia form parts of the maxillae. The palp is a five segmented, sensory organ concerned with taste. The labium is the lower lip. Cockroaches have no lungs, hence they respire through spiracles. Cockroaches are unisexual. They exhibit sexual dimorphism. The hypopharynx serves as a tongue in the cockroach. 10 pairs of spiracles are present in an adult cockroach which are meant for respiration. In a cockroach, excretion is done by Malpighian tubules. In each insect, there are about 150 Malpighian tubules. Cockroaches have a multi-chambered heart.
Hence, the correct answer is option B.

Note: Periplaneta americana is the largest and common species of cockroach. This species of cockroach is considered a pest. The cockroaches are an ancient group, dating back at least as far as the Carboniferous period, some 320 million years ago. These organisms can cause many food-related diseases.