Question

Why do moss plants produce very large number of male gametes? Provide one reason. What are these gametes called?

Answer 1

They use water for the transfer of male gametes to the female gametes. Hence, during this process, many male gametes get destroyed or lost. Due to this male gametes are produced in a bunk so that if some get destroyed or lost there may some that can reach the female gamete and result in the fertilisation. 
Male gametes of moss plants are called sperms and female gametes are called eggs.