Assertion : Protandry and protogyny ensure cross fertilisation in some animals. Reason: Cross fertilisation introduces variation in progeny.

Step-by-step solution

Most of the sexually reproducing animals are either males or females. But in some lower animals, the organs of both the sexes are found in the same individual. These are called bisexual or monoecious animals or hermaphrodites. In these animals, testes and ovaries do not mature simultaneously. In some, testes mature earlier, while in others, ovaries mature earlier. These conditions are respectively called protandry and protogyny. They ensure cross fertilisation. Cross fertilisation is a process in which gametes deri