L2 - Reproduction and Mutations

• Sexual reproduction


  This type of reproduction involves 2 parents and results in offspring being genetically different from parents. This is because the offspring have a new combination of chromosomes from both parents. USES MEIOSIS.
• Asexual reproduction


  This type of reproduction involves only one parent and results in offspring which are genetically identical to the parent e.g. a bacterium copying itself and dividing to produce clones. USES MITOSIS.
• Mutations result in a change in the sequence of bases on DNA e.g. a thymine could be replaced by a guanine.
• Most mutations have no effect but some can be harmful or beneficial.
• The rate of mutation is increased by ionising radiation such as UV light, X-rays and gamma rays.