Question

The enzyme found in the saliva of cockroach is
(a) Amylase
(b) Cellulase
(c) Protease
(d) Both a and b

Answer 1

Hint: Enzyme found in the saliva of cockroach is released by a pair of salivary glands. They help in the digestion of various complex carbohydrates. They are present in all the vertebrates and some fungi and prokaryotes.

Complete step by step answer:
Digestion in the cockroach begins in the pre- oral cavity of the foregut of its alimentary canal. The pre- oral cavity, as its name suggests, is a space which is in front of the mouth to receive food. It is bounded by the labrum anteriorly and labium posteriorly. Mandible and maxilla lateral bound pre- oral cavity. A tongue- like structure called hypopharynx projects from the posterior wall of the cavity. There are two salivary glands present in the cockroach. These salivary glands release their secretion with the help of a common salivary duct. These secretions are also known as saliva and are composed of enzymes like amylase, chitinase, and cellulase for the partial digestion of carbohydrates.
So, the correct answer is ‘(d) Both a and b.’

Additional Information:
- Cellulase catalyzes cellulolysis or the cleavage and decomposition of cellulose into its monosaccharides which are beta- glucose. This enzyme is produced in abundant concentrations by various fungi, bacteria, and termites.
- Amylase breaks down the complex carbohydrates like starch into disaccharides. The starch is a polysaccharide of linear amylose and branched amylopectin.
- The digestive secretions are secreted by the midgut of the alimentary canal in the cockroach. It contains enzymes like trypsin, proteases, and peptidases which help in the digestion of proteins.
- Proteases, trypsin, and peptidases are the enzymes that are released in the digestive secretions.

Note:
- Labrum is a broad, movable, and rectangular plate which behaves as an upper lip in the cockroach. It serves to hold the food.
- Labium is a broad plate which bears many sensory bristles and acts as a lower lip. It prevents the falling of food particles and pushes the food in the mouth.
- Mandibles are one pair of highly rough triangular structures which have teeth like denticles. These help in grinding the food.
- Each maxilla acts as accessory jaws. They also serve to clean the antennae and the foreleg.