Question

What will happen if gametes and bodycells have the same number of chromosomes?

Answer 1

 Actually it is possible. Sometimes, during meiosis (the process by which gametes are formed), when the chromosomes line up they don't split into the two new cells evenly. One cell gets all of them, and the other cell gets none. So one cell has the same number of chromosomes as a body cell. 

If this happens, when that gamete, which has twice the number of chromosomes than it should, combines with another gamete, which has the right number of chromosome, the offspring will have the normal duplicate set of chromosomes (like in body cells) and an extra 3rd set of chromsomes. 

The offspring will either die or be sterile/otherwise horribly affected by the presence of the 3rd extra set of chromosomes.

Answer 2

If gametes carry same number of chromosomes as body cells, then after every generation chromosome number will double because gametes fuse to form a zygote from which a new organism will be formed. Such an organism with 12 chromosome in body cells,...