Page 86 - Science

• After the last egg has been laid, the

incubation process begins.

• One or both parents, in turns, sit on

the eggs to keep them warm.

• In a fetilised egg, a disc of tissue

forms on the yolk and uses the food

stored in it to form the chick.

• When this process is complete, the

chick bursts into the air space and

then chips its way out of the shell.