During spermatogenesis, chromosome no. reduces to haploid at:-
The first meiotic division is known as the reduction division in which each primary spermatocyte yields two secondary spermatoctyes. Each contains 23 (Haploid) chromosomes consist of two varieties 22+X and 22+Y. Here 22 are autosomes and X & Y are sex chromosomes.
At mitosis
Meiosis -I
Meiosis-II
None of above
Introduction and gametogenesis.