meosis

• Describe how crossing over in meiosis leads to genetic variation.

  During meiosis 1, homologous chromosomes twist around each other. Then, portions of alleles are exchanged and this produces a new combination of alleles in each chromosome. 
• Describe how independent segregation in meiosis leads to genetic variation.

  During meiosis 1, the homologous chromosomes line up at random. This creates different combinations of chromosomes

   

   
• Describe how non-disjunction in meiosis leads to genetic variation.

  In meiosis 1, non-disjunction can stop the homologous pairs of chromosomes from separating. In meiosis 2, it can stop the sister chromatids from separating. Both cases result in gametes with an unequal number of chromosomes. 

   
• Name three processes which can result in genetic variation during meiosis.

  1. Crossing over
  2. Independent segregation
  3. Non-disjunction
• Describe the process of crossing over and explain how it increases genetic diversity

  during crossing over the chromatids get twisted around each other meaning that a portion from each homologous pair is exchanged. . This means that the alleles are exchanged and increases genetic diversity because of new combinations
• What is the biological importance of reducing the chromosomes number when the cell divides by mitosis?

  fusions causes the number of chromosomes to double.Meiosis ensures that fusion leads to the diploid number of chromosomes.