enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Sister chromatids - Wikipedia

    en.wikipedia.org/wiki/Sister_chromatids

    A full set of sister chromatids is created during the synthesis (S) phase of interphase, when all the chromosomes in a cell are replicated. The two sister chromatids are separated from each other into two different cells during mitosis or during the second division of meiosis. Compare sister chromatids to homologous chromosomes, which are the ...

  3. Centromere - Wikipedia

    en.wikipedia.org/wiki/Centromere

    In this diagram of a duplicated chromosome, (2) identifies the centromere—the region that joins the two sister chromatids, or each half of the chromosome. In prophase of mitosis, specialized regions on centromeres called kinetochores attach chromosomes to spindle fibers. The centromere links a pair of sister chromatids together during cell ...

  4. Polytene chromosome - Wikipedia

    en.wikipedia.org/wiki/Polytene_chromosome

    In insects, polytene chromosomes are commonly found in the salivary glands; they are also referred to as "salivary gland chromosomes". The large size of the chromosome is due to the presence of many longitudinal strands called chromonemata; hence the name polytene (many stranded). They are about 0.5 mm in length and 20 μm in diameter.

  5. Chromatid - Wikipedia

    en.wikipedia.org/wiki/Chromatid

    A chromatid (Greek khrōmat- 'color' + -id) is one half of a duplicated chromosome. Before replication, one chromosome is composed of one DNA molecule. In replication, the DNA molecule is copied, and the two molecules are known as chromatids. [1] During the later stages of cell division these chromatids separate longitudinally to become ...

  6. Bivalent (genetics) - Wikipedia

    en.wikipedia.org/wiki/Bivalent_(genetics)

    Bivalent (genetics) In cellular biology, a bivalent is one pair of chromosomes (homologous chromosomes) in a tetrad. A tetrad is the association of a pair of homologous chromosomes (4 sister chromatids) physically held together by at least one DNA crossover. This physical attachment allows for alignment and segregation of the homologous ...

  7. Cell division - Wikipedia

    en.wikipedia.org/wiki/Cell_division

    The cell cycle in eukaryotes: I = Interphase, M = Mitosis, G 0 = Gap 0, G 1 = Gap 1, G 2 = Gap 2, S = Synthesis, G 3 = Gap 3. Cell division is the process by which a parent cell divides into two daughter cells. [ 1 ] Cell division usually occurs as part of a larger cell cycle in which the cell grows and replicates its chromosome (s) before ...

  8. Cell nucleus - Wikipedia

    en.wikipedia.org/wiki/Cell_nucleus

    Centrosome. Cell membrane. The cell nucleus (from Latin nucleus or nuculeus 'kernel, seed'; pl.: nuclei) is a membrane-bound organelle found in eukaryotic cells. Eukaryotic cells usually have a single nucleus, but a few cell types, such as mammalian red blood cells, have no nuclei, and a few others including osteoclasts have many.

  9. Mitosis - Wikipedia

    en.wikipedia.org/wiki/Mitosis

    Mitosis (/ maɪˈtoʊsɪs /) is a part of the cell cycle in which replicated chromosomes are separated into two new nuclei. Cell division by mitosis is an equational division which gives rise to genetically identical cells in which the total number of chromosomes is maintained. [ 1 ]