For the second question on the production of sister chromatids, I suppose the first thing we need to figure out is what is sister chromatid. A Sister chromatid is either of the two identical copies of chromatids and the chromatid is formed by the replication of a single chromosome. During the process of the replication of a single chromosome, both copies of chromatids joined together by a centromere, which is a part of a chromosome that connects sister chromatids. Therefore, we can also regard a sister chromatid as a half of the duplicated chromosome. A full set of sister chromatids is produced when all the chromosomes in a cell are replicated. This process takes place during the synthesis phase of interphase. Interphase is one of the phases of the cell cycle and there are three stages of interphase; synthesis is one of the stages of interphase. During synthesis, the cell duplicates its DNA. According to the analysis of the second question, I think that the second …show more content…
Although homologous chromosomes contain the same genes, they can have different alleles of the same gene. An allele refers to one of plenty of alternative forms of the same gene. For example, a set of homologous chromosomes explain eye color. One of the chromosomes genes explains blue eyes, and the other one explains brown eyes. This is the