Question

why do we need meiosis?
to not change the number of chromosomes going into sex cells
to double the number of chromosomes going into sex cells
to triple the number of chromosomes going into sex cells
to halve the number of chromosomes going into sex cells

Explanation:

Meiosis is a type of cell division that reduces the chromosome number by half. This is crucial for sexual reproduction. When gametes (sex cells) are formed through meiosis, they have half the number of chromosomes of the parent cell. During fertilization, when a sperm (male gamete) and an egg (female gamete) fuse, the resulting zygote has the full complement of chromosomes (the original number of the parent organism before meiosis in the cells that give rise to gametes). If meiosis did not halve the chromosome number in gametes, each generation would have double the number of chromosomes of the previous generation.

Answer:

To halve the number of chromosomes going into sex cells.