meiosis

    Cards (29)

    • What is the purpose of meiosis?
      To produce haploid gametes for reproduction
    • What occurs during Meiosis I?
      • Homologous chromosomes pair up
      • Crossing over occurs
      • Homologous chromosomes separate
      • Chromosome number is halved
    • What happens to homologous chromosomes during prophase I of meiosis?
      They pair up and exchange genetic material
    • What is the outcome of homologous chromosomes separating during meiosis I?
      Chromosome number is halved
    • How does Meiosis II compare to mitosis?
      • Similar process to mitosis
      • Sister chromatids separate
      • Results in four haploid cells
    • How many haploid cells are produced at the end of meiosis?
      Four haploid cells
    • What are the sources of genetic variation in meiosis?
      • Crossing over
      • Independent assortment
      • Random fertilization
    • What is crossing over in meiosis?
      Exchange of genetic material between homologous chromosomes
    • What is independent assortment in meiosis?
      Random distribution of maternal and paternal chromosomes
    • What does random fertilization refer to in meiosis?
      Different gametes combine at fertilization
    • What are the key features of meiosis?
      • Produces four genetically different haploid gametes
      • Used in sexual reproduction
      • Involves two rounds of division (meiosis I and II)
    • What is the first stage of meiosis called?
      Meiosis I
    • What happens during Prophase I of meiosis?
      • Chromosomes condense and become visible
      • Homologous chromosomes pair up (synapsis)
      • Crossing over occurs at chiasmata
      • Nuclear envelope breaks down
      • Spindle fibers form
    • What is the process called when homologous chromosomes pair up?
      Synapsis
    • What occurs during crossing over in Prophase I?
      Exchange of genetic material between non-sister chromatids
    • What happens to the nuclear envelope during Prophase I?
      It breaks down
    • What forms during Prophase I of meiosis?
      Spindle fibers
    • What occurs during Metaphase I of meiosis?
      • Bivalents align along the metaphase plate
      • Independent assortment occurs
      • Spindle fibers attach to centromeres of homologous chromosomes
    • What is independent assortment in Metaphase I?
      Random orientation of each bivalent
    • What happens to homologous chromosomes during Anaphase I?
      They are pulled to opposite poles
    • What remains attached during Anaphase I?
      Sister chromatids
    • What occurs during Telophase I and Cytokinesis?
      • Nuclear envelope may reform briefly
      • Cell divides into two haploid cells
      • Each chromosome still has two sister chromatids
    • What is the second stage of meiosis called?
      Meiosis II
    • How does Meiosis II differ from Meiosis I?
      • Similar to mitosis
      • Starts with haploid cells
    • What happens during Prophase II of meiosis?
      • Chromosomes condense again
      • Spindle fibers form
    • What occurs during Metaphase II of meiosis?
      • Chromosomes line up individually
      • Spindle fibers attach to centromeres of sister chromatids
    • What happens during Anaphase II?
      Sister chromatids separate and move to opposite poles
    • What occurs during Telophase II and Cytokinesis?
      • Nuclear envelopes reform
      • Cytoplasm divides
      • Result: Four genetically different haploid daughter cells
    • How many genetically different haploid daughter cells are produced at the end of meiosis?
      Four