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  2. Meiosis - Wikipedia

    en.wikipedia.org/wiki/Meiosis

    The four main steps of meiosis II are: prophase II, metaphase II, anaphase II, and telophase II. In prophase II, we see the disappearance of the nucleoli and the nuclear envelope again as well as the shortening and thickening of the chromatids. Centrosomes move to the polar regions and arrange spindle fibers for the second meiotic division.

  3. Metaphase - Wikipedia

    en.wikipedia.org/wiki/Metaphase

    Metaphase (from Ancient Greek μετα- (meta-) beyond, above, transcending and from Ancient Greek φάσις (phásis) 'appearance') is a stage of mitosis in the eukaryotic cell cycle in which chromosomes are at their second-most condensed and coiled stage (they are at their most condensed in anaphase). [ 1 ] These chromosomes, carrying ...

  4. Chromosomal crossover - Wikipedia

    en.wikipedia.org/wiki/Chromosomal_crossover

    Chromosomal crossover, or crossing over, is the exchange of genetic material during sexual reproduction between two homologous chromosomes ' non-sister chromatids that results in recombinant chromosomes. It is one of the final phases of genetic recombination, which occurs in the pachytene stage of prophase I of meiosis during a process called ...

  5. Prophase - Wikipedia

    en.wikipedia.org/wiki/Prophase

    Prophase (from Ancient Greek προ- (pro-) 'before' and φάσις (phásis) 'appearance') is the first stage of cell division in both mitosis and meiosis. Beginning after interphase, DNA has already been replicated when the cell enters prophase. The main occurrences in prophase are the condensation of the chromatin reticulum and the ...

  6. Folliculogenesis - Wikipedia

    en.wikipedia.org/wiki/Folliculogenesis

    Until the preovulatory stage, the follicle contains a primary oocyte that is arrested in prophase of meiosis I. During the late preovulatory stage, the oocyte continues meiosis and becomes a secondary oocyte, arrested in metaphase II. (a) The maturation of a follicle is shown in a clockwise direction proceeding from the primordial follicles.

  7. Chiasma (genetics) - Wikipedia

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

    Crossing over during meiosis, with chiasma shown. In genetics, a chiasma (pl.: chiasmata) is the point of contact, the physical link, between two (non-sister) chromatids belonging to homologous chromosomes. At a given chiasma, an exchange of genetic material can occur between both chromatids, what is called a chromosomal crossover, but this is ...

  8. Spindle checkpoint - Wikipedia

    en.wikipedia.org/wiki/Spindle_checkpoint

    The spindle checkpoint, also known as the metaphase-to-anaphase transition, the spindle assembly checkpoint (SAC), the metaphase checkpoint, or the mitotic checkpoint, is a cell cycle checkpoint during metaphase of mitosis or meiosis that prevents the separation of the duplicated chromosomes until each chromosome is properly attached to the ...

  9. 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 ...