Question

gametes must be produced by meiosis for sexual reproduction.why is it so ?

Answer 1

Mitosis takes place in diploid human somatic cells, where the number of chromosomes and the genetic content is required to stay the same. In gamete formation, the number of chromosomes must be halved, because gametes are required to be haploid. Thus meiosis, a form a reductive cell division occurs. This is to balance the doubling effect which fertilisation has on chromosome number. During meiosis, genetic information is exchanged between chromosomes, during crossing over. This, along with random assortment, introduces genetic variation, which is important for the survival of the species.

Answer 2

Explanation:

In gamete formation the number of chromosomes must be half because gametes are required to be haploid .This is to balance the rubbing effect which fertilization has on chromosome number .