This diagram shows an animal cell in meiosis I during crossing over and synapsis. A single tetrad is shown with a pair of homologous chromosomes that have been duplicated as sister chromatids. Red chromosomes indicate maternal DNA, and blue chromosomes indicate paternal DNA. Use the passage to answer the question. Once the animal cell has completed meiosis II:
The animal cell has completed meiosis II when the process of separation of sister chromatids has occurred, resulting in the production of four haploid daughter cells. This process follows meiosis I, which involves the crossing over and synapsis of homologous chromosomes.
During meiosis I, homologous chromosomes (one from each parent) come together in a process called synapsis and form a structure called a tetrad. This allows for the exchange of genetic material between the homologous chromosomes, known as crossing over. Cross over leads to genetic diversity in offspring.
After synapsis and crossing over in meiosis I, the homologous chromosomes separate during meiosis II. Sister chromatids, which were duplicated during the S phase of the cell cycle, now separate and migrate towards opposite poles of the cell. This process is similar to the separation of chromosomes during mitosis.
As a result of this division, four haploid daughter cells are produced, each with half the number of chromosomes as the original parent cell. These daughter cells are genetically distinct from each other and from the parent cell due to crossing over and independent assortment of chromosomes.
Therefore, once the animal cell has completed meiosis II, it has undergone two rounds of cell division resulting in the formation of four genetically diverse haploid daughter cells.