Question

If the sex cell of an organism has 20 chromosomes, then the body cells will have:

Answer 1

Answer: 40 body cells

Why?  The sex cells are formed during gametogenesis as a consequence of meiotic divisions. Thus the sex cells will be haploid (having half the number of chromosomes of diploid body cells).

So, 20 * 2 = 40

Hope this helped :)