Reproduction, Development and Growth — BIOLOGY STD 8 — Question

In insects, such butterflies, fertilized eggs are laid. A caterpillar hatches out from an egg. The caterpillar looks more like a worm than like a butterfly. A Caterpillar of a butterfly is called the larva. A larva eats a large quantity of leaves and grows larger until its skin bursts. A new and larger caterpillar comes out and continues to eat and grow. The process of casting off the old skin while growing is called moulting. The caterpillar then produces an outer covering called a cocoon around itself.

Inside the cocoon, the organism begins the next stage of its life cycle, called the pupa. Sometimes the pupa is called a resting stage but it is not a time of rest. There are many changes which take place inside the cocoon. Within the cocoon, the tissues of the larva reorganize to form the butterfly. Finally the cocoon breaks open and the adult butterfly comes out.