11
State the number of segments in earthworm which are covered by a prominent dark band or clitellum.
Explanation
Segments 14-16 are covered by a prominent dark band of glandular tissue called clitellum in a mature earthworm.
Which secretes mucus and albumen that help in formation of cocoon and is used for fertilisation of eyes and sperms.
12
Where are sclerites present in cockroach?
Explanation
Sclerites are present in all the body segments of cockroach. These are of two types Dorsal sclerites often known as tergites, and Ventral sclerites which are referred to as sternites.
13
How many times do nymphs moult to reach the adult form of cockroach?
Explanation
The nymph grows by moulting about 13 times to reach. In cockroach, the development is indirect and paurometabous adult form and has three stages. i.e., egg, nymph and adult. The nymph resembles adult except for undeveloped wings and genitalia.
14
Identify the sex of a frog in which sound producing vocal sacs are present.
Explanation
In amphibians, sex of frogs can be distinguished with the presence of sound producing vocal sacs. These organs are present in males which make them crock lauder, than females, so as to attract females for mating.
15
Name the process by which a tadpole develops into an adult frog.
Explanation
Tadpole undergoes metamorphosis to form adult.
