Question

At the point in the cell cycle when mitosis begins 2 points A. the chromatids have separated into two identical chromosomes. B. DNA replication begins. C. each chromosome consists of two identical chromatids joined at the centromere. D. chromosome number is halved. E. the cell enters a dormant phase

Answer 1

At the point when mitosis begins, each chromosome consists of two identical chromatids joined at the centromere, which is after DNA replication during the S phase of the cell cycle.

Step-by-step explanation:

At the point in the cell cycle when mitosis begins, the correct statement is C. each chromosome consists of two identical chromatids joined at the centromere. This is because, prior to mitosis, the cell has undergone the S phase (synthesis phase) during which DNA replication occurs, resulting in the formation of sister chromatids for each chromosome. These sister chromatids are attached at their respective centromeres, effectively forming one chromosome. As mitosis progresses through its four distinct phases - prophase, metaphase, anaphase, and telophase - the sister chromatids will eventually separate and be pulled to opposite poles of the cell.

In prophase, chromosomes condense and become visible. During metaphase, chromosomes line up in the center of the cell. In anaphase, the sister chromatids separate and move to opposite poles, and during telophase, the nuclear envelope re-forms around each set of chromosomes.