Variation

• Variation

  There are differences in characteristics between members of the same species
• Variation can be

  • Acquired during life of organism (riding a bike)
  • Inherited/genetic: can be passed on to the next generation by sexual reproduction (tongue rolling)
• Sexual reproduction

  Responsible for most of variation that are in offspring
• Variation caused by sexual reproduction reasons

  1. Independent assortment: to the way in which chromosomes enter into gametes at meiosis
  2. Crossing over of chromosomes: this produces a combination of genes from the mother and father
  3. Recombination: at fertilisation each egg and sperm represents a one in eight million combination of chromosomes, which shows that sexual reproduction produces a huge range of genetic variation