Before mitosis begins, which happens before the nucleus starts diving? A. The cytoplasm separates.

B. The DNA replicates.

C. The sister chromatids separate.

D. The homologous chromosomes cross over.

B. The DNA replicates.

Explanation:

Activity in the chromosomes must occur before the beginning of mitosis. The cells will enter the S1 phase in preparation to divide.

B should be your answer

Explanation:

photosynthesis makes the glucose that is used in cellular respiration to make atp. the glucose is then turned back into carbon dioxide, which is used in photosynthesis. while water is broken down to form oxygen during photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water.