At the end of the mitotic cell cycle, a cell divides into two cells. What must happen before the cell divides? A. The number of organelles doubles. B. Chromosomes must be copied. C. Four nuclei must be formed. D. The membrane thickens.

The correct option is B.

B. Chromosomes must be copied

Explanation:

This is because, before mitosis occurs the cells must first duplicate or replicate it's DNA during interphase and this is because mitosis is a type of cell division where a parent cell divide into two daughter cells which are genetically identical to the parent cell and carry the exact number of chromosomes of the parent cell.

cuz he's blad

explanation:

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.