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  2. Origin and function of meiosis - Wikipedia

    en.wikipedia.org/wiki/Origin_and_function_of_meiosis

    Even in multicellular eukaryotes, such as humans, oxidative stress is a problem for cell survival. In this case, oxidative stress is a byproduct of oxidative cellular respiration occurring during metabolism in all cells. In humans, on average, about 50 DNA double-strand breaks occur per cell in each cell generation. [21]

  3. Sexual reproduction - Wikipedia

    en.wikipedia.org/wiki/Sexual_reproduction

    Some proteins and other features that are key for sexual reproduction may have arisen in bacteria, but sexual reproduction is believed to have developed in an ancient eukaryotic ancestor. [10] In eukaryotes, diploid precursor cells divide to produce haploid cells in a process called meiosis. In meiosis, DNA is replicated to produce a total of ...

  4. Meiosis - Wikipedia

    en.wikipedia.org/wiki/Meiosis

    This is an accepted version of this page This is the latest accepted revision, reviewed on 26 January 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 ...

  5. Reproduction - Wikipedia

    en.wikipedia.org/wiki/Reproduction

    Sexual reproduction is a biological process that creates a new organism by combining the genetic material of two organisms in a process that starts with meiosis, a specialized type of cell division. Each of two parent organisms contributes half of the offspring's genetic makeup by creating haploid gametes . [ 8 ]

  6. Eukaryote - Wikipedia

    en.wikipedia.org/wiki/Eukaryote

    The origin of the eukaryotic cell, or eukaryogenesis, is a milestone in the evolution of life, since eukaryotes include all complex cells and almost all multicellular organisms. The last eukaryotic common ancestor (LECA) is the hypothetical origin of all living eukaryotes, [ 71 ] and was most likely a biological population , not a single ...

  7. Zygote - Wikipedia

    en.wikipedia.org/wiki/Zygote

    A zygote (/ ˈ z aɪ ˌ ɡ oʊ t /; from Ancient Greek ζυγωτός (zygōtós) 'joined, yoked', from ζυγοῦν (zygoun) 'to join, to yoke') [1] is a eukaryotic cell formed by a fertilization event between two gametes. The zygote's genome is a combination of the DNA in each gamete, and contains all of the genetic information of a new ...

  8. Evolution of sexual reproduction - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_sexual...

    These proteins could have been transferred to the cell membrane during viral reproduction, enabling cell-to-cell fusion between the virus host and an uninfected cell. The theory proposes meiosis originated from the fusion between two cells infected with related but different viruses which recognised each other as uninfected.

  9. Cell (biology) - Wikipedia

    en.wikipedia.org/wiki/Cell_(biology)

    Some eukaryotic cells (plant cells and fungal cells) also have a cell wall. Inside the cell is the cytoplasmic region that contains the genome (DNA), ribosomes and various sorts of inclusions. [2] The genetic material is freely found in the cytoplasm. Prokaryotes can carry extrachromosomal DNA elements called plasmids, which are usually circular.