Answer:
After S phase sister chromatids appear to share a common centromere.
Explanation:
The cells of the different organisms go through different periods during their life, each one characteristic and well differentiated. Before the mitosis process, during the S phase of the cell cycle, the chromosomes replicate, so that at the time of initiating cell division in humans, each of the 46 replicated chromosomes will have two chromatids joined by the centromere, each one of them represents a functional chromosome. Each sister chromatid of a chromosome secretes a daughter cell, as do the other 45, and together they will make up the diploid "cluster" of 46 chromosomes from the new cell. In other words, each chromosome is made up of two chromatids that come together at a point called the centromere. One chromatid contains a condensed chromatin molecule and the other has another identical chromatin molecule, the result of DNA replication, which is why we talk about a sister chromatid chromosome. Each chromatid has two arms of equal or different length.
