Meiosis has 2 divisions

• what is meiosis 1 sometimes called?

  a ‘reduction division’
• why is meiosis 1 sometimes called a ‘reduction division’?

  as it halves the chromosomes number in each cell
• what is a summary of what happens in meiosis?

  • DNA replication in interphase is followed by 2 divisions, meiosis 1 and 2
  • each division goes through the same sequence of steps as mitosis but the chromosomes behave differently
  • between the 2 divisions theres no more DNA replication, only happens once before meiosis 1
  • by the end of meiosis 1, the homologous pairs of chromosomes have separated
  • in meiosis 2, chromatids separate and the nuclei divides again
  • 4 haploid nuclei are formed, each containing 1/2 the number of chromosomes
• what is the main thing that happens in meiosis 1?

  the homologous chromosomes separate
• what is the main thing that happens in meiosis 2?

  the chromatids seperate
• why are the names of the stages followed by 1 or 2 in meiosis?

  to distinguish the 2 divisions as the chromosomes behave differently
• how many times does DNA replication happen in meiosis?

  once
• when does DNA replication happen in meiosis?

  before meiosis 1
• what happens at the end of meiosis 1?

  the homologous pairs of chromosomes have separated, with one chromosome of each pair going into either of the 2 daughter cells
• how many chromosomes does each daughter cell have?

  each daughter cell has only one of each homologous pair, so they contain half the number of chromosomes of the parent nucleus
• what happens to the chromatids in meiosis 2?

  they separate and the 2 new haploid nuclei divide again
• what do the 4 haploid nuclei contain at the end of meiosis 2?

  they contain half the number of chromosomes and every gamete is genetically unique
• what is this a diagram of?

  the stages of meiosis