enow.com Web Search

Search results

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

    en.wikipedia.org/wiki/Meiosis

    Meiosis I segregates homologous chromosomes, which are joined as tetrads (2n, 4c), producing two haploid cells (n chromosomes, 23 in humans) which each contain chromatid pairs (1n, 2c). Because the ploidy is reduced from diploid to haploid, meiosis I is referred to as a reductional division .

  3. Chromosome 3 - Wikipedia

    en.wikipedia.org/wiki/Chromosome_3

    Chromosome 3 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. People normally have two copies of this chromosome. Chromosome 3 spans more than 198 million base pairs (the building material of DNA ) and represents about 6.5 percent of the total DNA in cells .

  4. Genetic recombination - Wikipedia

    en.wikipedia.org/wiki/Genetic_recombination

    Gene conversion has often been studied in fungal crosses [8] where the 4 products of individual meioses can be conveniently observed. Gene conversion events can be distinguished as deviations in an individual meiosis from the normal 2:2 segregation pattern (e.g. a 3:1 pattern).

  5. Leptotene stage - Wikipedia

    en.wikipedia.org/wiki/Leptotene_stage

    During the leptotene stage, the duplicated chromosomes - each consisting of two sister chromatids - condense from diffuse chromatin into long, thin strands that are more visible within the nucleoplasm (nucleus contents). The chromosomes become visible as thin threadlike structures known as leptonema under a light microscope. [1]: 27 [2]: 353

  6. Pachytene - Wikipedia

    en.wikipedia.org/wiki/Pachytene

    The pachytene stage (/ˈpækɪtiːn/ PAK-i-teen; from Greek words meaning "thick threads". [1]: 27 ), also known as pachynema, is the third stage of prophase I during meiosis, the specialized cell division that reduces chromosome number by half to produce haploid gametes.

  7. Origin and function of meiosis - Wikipedia

    en.wikipedia.org/wiki/Origin_and_function_of_meiosis

    The two chromosomes which pair are referred to as non-sister chromosomes, since they did not arise simply from the replication of a parental chromosome. Recombination between non-sister chromosomes at meiosis is known to be a recombinational repair process that can repair double-strand breaks and other types of double-strand damage. [2]

  8. Chromosomal crossover - Wikipedia

    en.wikipedia.org/wiki/Chromosomal_crossover

    Crossing over is important for the normal segregation of chromosomes during meiosis. [2] Crossing over also accounts for genetic variation, because due to the swapping of genetic material during crossing over, the chromatids held together by the centromere are no longer identical. So, when the chromosomes go on to meiosis II and separate, some ...

  9. Chiasma (genetics) - Wikipedia

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

    [3] [4] 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.