EVERYDAY SCIENCE

Detailed explanation-1: -The statement (a) is incorrect because Malpighian tubules are excretory structures in most of the insects, including cockroach, but green glands perform excretory functions in crustaceans like prawns, whereas all the other statements are true.

Detailed explanation-2: -Malpighian tubules are slender tubes normally found in the posterior regions of arthropod alimentary canals. Each tubule consists of a single layer of cells that is closed off at the distal end with the proximal end joining the alimentary canal at the junction between the midgut and hindgut.

Detailed explanation-3: -Malpighian tubules are excretory organs of insects. These are unbranched tubules lying almost freely in the haemocoel and open into the alimentary canal. The main function of these tubules is to absorb nitrogenous waste products. Spiracles are the respiratory systems of insects through a series of external openings.

Detailed explanation-4: -In certain insects, the Malpighian tubules are modified. For instance, the Malpighian tubules of the larvae of the glowworm, Arachnocampa luminosa, are capable of emitting a blue-green light that attract prey.