This process is known as cytokinesis. Meiosis II 6. Prophase II: Now there are two daughter cells, each with 23 chromosomes 23 pairs of chromatids. In each of the two daughter cells the chromosomes condense again into visible X-shaped structures that can be easily seen under a microscope. The membrane around the nucleus in each daughter cell dissolves away releasing the chromosomes. The centrioles duplicate. The meiotic spindle forms again. Metaphase II: In each of the two daughter cells the chromosomes pair of sister chromatids line up end-to-end along the equator of the cell.
The centrioles are now at opposites poles in each of the daughter cells. Meiotic spindle fibres at each pole of the cell attach to each of the sister chromatids.
Anaphase II: The sister chromatids are then pulled to opposite poles due to the action of the meiotic spindle. The separated chromatids are now individual chromosomes.
Telophase II and cytokinesis: The chromosomes complete their move to the opposite poles of the cell. A membrane forms around each set of chromosomes to create two new cell nuclei. This is the last phase of meiosis, however cell division is not complete without another round of cytokinesis. Once cytokinesis is complete there are four granddaughter cells, each with half a set of chromosomes haploid : in males, these four cells are all sperm cells in females, one of the cells is an egg cell while the other three are polar bodies small cells that do not develop into eggs.
Related Content:. What is a cell? What is a chromosome? What is mitosis? What is DNA? Mitosis versus meiosis. What is a genetic disorder? How helpful was this page? Share this comparison:. If you read this far, you should follow us:. Diffen LLC, n. All organisms. No, crossing over cannot occur. Definition A type of cellular reproduction in which the number of chromosomes are reduced by half through the separation of homologous chromosomes, producing two haploid cells. A process of asexual reproduction in which the cell divides in two producing a replica, with an equal number of chromosomes in each resulting diploid cell.
Cellular reproduction and general growth and repair of the body. Remains the same. Prophase, Metaphase, Anaphase, Telophase. Karyokinesis Occurs in Interphase I. Occurs in Interphase. Occurs in Telophase. The centromeres split during anaphase. Creates Sex cells only: female egg cells or male sperm cells. Makes everything other than sex cells. Discovered by Oscar Hertwig Walther Flemming.
Differences in Purpose What is the role and purpose of mitosis and meiosis? Meiosis and Genetic Diversity Sexual reproduction uses the process of meiosis to increase genetic diversity. Follow Share Cite Authors. Share this comparison: If you read this far, you should follow us: "Mitosis and Meiosis. Meiosis is a type of cell division that reduces the number of chromosomes in the parent cell by half and produces four gamete cells.
This process is required to produce egg and sperm cells for sexual reproduction. During reproduction, when the sperm and egg unite to form a single cell, the number of chromosomes is restored in the offspring.
Meiosis begins with a parent cell that is diploid, meaning it has two copies of each chromosome. The parent cell undergoes one round of DNA replication followed by two separate cycles of nuclear division. The process results in four daughter cells that are haploid, which means they contain half the number of chromosomes of the diploid parent cell.
Meiosis has both similarities to and differences from mitosis, which is a cell division process in which a parent cell produces two identical daughter cells. Meiosis begins following one round of DNA replication in cells in the male or female sex organs. The process is split into meiosis I and meiosis II, and both meiotic divisions have multiple phases.
Meiosis I is a type of cell division unique to germ cells, while meiosis II is similar to mitosis. Meiosis I, the first meiotic division, begins with prophase I.
During prophase I, the complex of DNA and protein known as chromatin condenses to form chromosomes. The pairs of replicated chromosomes are known as sister chromatids, and they remain joined at a central point called the centromere.
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