Question

why does the meiosis produce cells with only half the amount of DNA? How does this aid in the formation of a healthy zygote?

Answer 1

Meiosis produces cells (germ cells or gametes) with only half the DNA, or chromosomes, as normal cells (somatic cells). This is called haploid or referred to as "n" number of chromosomes. Normal body cells have doubke that, called "2n," or diploid. For humans our n = 23, so germ cells (haploid) have only 23 chromosomes, while somatic (normal body) cells have "2n" or 46 chromosomes. It is important to only carry half the number of chromosomes or DNA (n), because it is going to combine with another half (n) when sperm meets egg during fertilization. This n + n = 2n restores the diploid number of chromosomes (DNA) in a zygote, the first cell of a future embryo, fetus, and new human being.