Question

Saliva of cockroach contains ______________ enzyme.
A) Lipase
B) Amylase
C) Pepsin
D) Trypsin

Answer 1

Saliva is an extracellular secretion secreted by several glands in mouth. Its main function is to lubricate the food and also initiate the process of digestion of dietary starch and fat but the enzymes pepsin and trypsin are involved in breakdown of proteins.

Complete Answer:
Cockroaches are omnivorous animals; they feed on a great variety of foodstuffs like bread, fruit, cardboard, paper, glue, leather, skin flakes, hair, dead insects and clothes. Cockroaches even show symbiotic association with protozoans and bacteria which digest cellulose present in their food and such symbionts are sometimes essential for utilization of cellulose which cannot digest it for themselves, some other species can digest it by their own, they secrete cellulase in their saliva, some of them are able to survive on just crystallized cellulose for an indefinite period. Cockroaches have a pair of labial glands which acts as salivary glands where the ducts of the gland open into salivarium, their saliva contains amylase for the digestion of starch.
Amylase is an enzyme which catalyses the hydrolysis of starch forming sugars. Amylase is present in the saliva and is responsible for beginning the chemical process of digestion. It converts the dietary starch into disaccharides and trisaccharides. Amylases are basically glycoside hydrolases which act on α-1,4-glycosidic bonds. Apart from animals, several plants also produce amylase.

Therefore, the correct answer is ‘B’. amylase.

Note: Cockroaches ingest a lot of food which consists of starch in it, amylase present in the saliva initiates the digestion of starch. While consuming food, they release some amount of saliva which when consumed by humans, causes several diseases.