複選題13. Which of the following statements about eukaryotic cell is true? (A) If a cell contains 20 chromosomes in G1 phase, it will contain 40 chromosomes at the end of S phase. (B)During prometaphase, the sister chromatids organize into a single row in the center of the cell. (C) One major difference between metaphase I and metaphase II is the presence or absence of bivalents. (D) Sister chromatids are produced during mitosis. (E)If environmental conditions are favorable during the G1 phase, G1 cyclins are degraded causing the cell to prepare to replicate its DNA.