enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Tetrad (meiosis) - Wikipedia

    en.wikipedia.org/wiki/Tetrad_(meiosis)

    Tetrad dissection has become a powerful tool of yeast geneticists, and is used in conjunction with the many established procedures utilizing the versatility of yeasts as model organisms. Use of modern microscopy and micromanipulation techniques allows the four haploid spores of a yeast tetrad to be separated and germinated individually to form ...

  3. Bivalent (genetics) - Wikipedia

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

    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 chromosomes in the first meiotic division.

  4. Chiasma (genetics) - Wikipedia

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

    When each tetrad, which is composed of two pairs of sister chromatids, begins to split, the only points of contact are at the chiasmata. The chiasmata become visible during the diplotene stage of prophase I of meiosis, but the actual "crossing-overs" of genetic material are thought to occur during the previous pachytene stage. Sister chromatids ...

  5. Heterothallism - Wikipedia

    en.wikipedia.org/wiki/Heterothallism

    Meiosis is an essential part of the life cycle of all sexually reproducing organisms, and in its main features, meiosis in N. crassa seems typical of meiosis generally. As the above events are occurring, the mycelial sheath that had enveloped the ascogonium develops as the wall of the perithecium, becomes impregnated with melanin, and blackens.

  6. Meiosis - Wikipedia

    en.wikipedia.org/wiki/Meiosis

    This is an accepted version of this page This is the latest accepted revision, reviewed on 16 February 2025. Cell division producing haploid gametes For the figure of speech, see Meiosis (figure of speech). For the process whereby cell nuclei divide to produce two copies of themselves, see Mitosis. For excessive constriction of the pupils, see Miosis. For the parasitic infestation, see Myiasis ...

  7. Meiocyte - Wikipedia

    en.wikipedia.org/wiki/Meiocyte

    A meiocyte is a type of cell that differentiates into a gamete through the process of meiosis. Through meiosis, the diploid meiocyte divides into four genetically different haploid gametes. [1] [2] The control of the meiocyte through the meiotic cell cycle varies between different groups of organisms.

  8. Gene conversion - Wikipedia

    en.wikipedia.org/wiki/Gene_conversion

    Gene conversion is the process by which one DNA sequence replaces a homologous sequence such that the sequences become identical after the conversion. [1] Gene conversion can be either allelic, meaning that one allele of the same gene replaces another allele, or ectopic, meaning that one paralogous DNA sequence converts another.

  9. Non-random segregation of chromosomes - Wikipedia

    en.wikipedia.org/wiki/Non-random_segregation_of...

    Non-random segregation of chromosomes is a deviation from the usual distribution of chromosomes during meiosis, that is, during segregation of the genome among gametes.While usually according to the 2nd Mendelian rule (“Law of Segregation of genes“) homologous chromosomes are randomly distributed among daughter nuclei, there are various modes deviating from this in numerous organisms that ...