Question

Peculiar pungent smell of cockroach is secretion of
a. Pheromone
b. Periplaneta
c. Dermal glands
d. Cervical glands

Answer 1

Chemicals produced by insects to attract the opposite sex for mating have strong and foul odour. These chemicals are named as pheromones also called as behavior altering agents. Dermal glands show wide variety in morphology. Cervical glands have lymph nodes which are responsible for various pathological functions. Pheromones play a very important role in cockroaches.

Complete answer:
Cockroach belongs to the order Blattodea. These are also called roaches. About 4,600 species are found that are among most primitive insects having wings. The word cockroach comes from Spanish word cucaracha. Habitats of the cockroach depend widely for example America cockroaches prefer to live in warm, dark, and wet areas. They can also be found in homes.

Pheromones are the chemicals secreted by cockroaches. These are secreted outside the body; they can affect the behavior of individuals. Pheromones can be used to communicate with other animals. Releaser, primer, signaler, and modulator are different types of pheromones found in individuals. Pheromones have a pungent smell which helps them to signaling, triggering sexual arousal, form bonds between mother and offspring and helps in warning other animals.

Dermal gland derived from epidermis is exocrine glands that show morphology, function and location based on common plans. Cervical glands or cervical lymph nodes are found in the neck. About 300 lymph nodes are found in the neck which can show several pathological conditions.

From the above information we can conclude that the peculiar pungent smell of cockroach is due to the secretion of pheromone.
Hence, the correct answer is option (A).

Note: First pheromone was identified in 1959. In the female moth Bombykol is secreted to attract males. Signals of pheromone can travel to a large distance even at low concentration. Pheromones can be detected by the organ in the nose and the organ is known as vomeronasal organ (VNO). This organ is also present in humans but as a pit that probably does not do anything. Humans use their olfactory system in response to any smell.