Why do the cells in meiosis have to divide twice?

Recall that the point of meiosis is to halve the genetic material in the cell for sexual reproduction (essentially the fusing of two cells). Humans are diploid meaning that we have two copies of our chromosomes within each cell, one copy from each parent. read more

So the cells begin meiosis with 4 copies of the set of “chromosomes”. Though because the replicated chromosomes pair up we say that they have 4 sister chromatids and still only two sets of chromosomes. read more

In meiosis, one cell divides twice in a row to form four daughter cells from one cell (Figure 1B). Those cells are then modified to become eggs or sperm. Mitosis and meiosis, then, are similar processes, but result in very different types of cells. read more