Variation

Created by: Owain
Created on: 03-01-13 17:50

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Variation
- Types of variation
  - Discontinuous
    - The information is put into a bar chart
    - This kind of variation is one of a number of groups
    - e.e. Blood groups or being able to roll your tongue
  - Continuous
    - e.e. Height, temperature or mass
    - The information is put into a histogram
- Reproduction
  - Sexual reproduction
    - Genetically unique gametes (sex cells) e.g. egg and sperm
    - Offspring genetically different from parents
    - There are 2 parents
    - Fertilization occurs joining 2 gametes to produce a new cell with a new set of pairs of chromosones
    - Leads to variation
  - Sexual reproduction
    - No gametes involved so nothing is fertilized
    - Offspring genetically identical to parent. Offspring called CLONES
    - 1 Parent
    - No variation in offspring
- Mutations
  - Some mutations are beneficial (helpful)
  - Mutations occur at random
  - Some mutations are dangerouse
  - Mutations are changes in the DNA of genes
  - Ionising radiation increase the rate of mutations
  - The greater the dose of the radiation, the greater the chance of mutation
  - Cystic fibrosis
    - Some mutations cause conditions which can be inherited like cystic fibrosis
    - Gene therapy
      - How does it work?
        The gene for normal mucus production must enter the lung tissue
        
        Getting the gene into the lungs of a sufferer of cystic fibrosis using an inhaler
        
        The cells produce a normal amount and thickness of mucus
        
        Finding, isolating and removing the gene for normal mucus production
      - Problem with gene therapy?
        The treatment is not a cure - it just makes symptoms better
        
        The genes might not express themselves (not work)
        
        It must be repeated regularly
        
        The genes might not enter the cells which produce mucus
      - Gene therapy is a temporary cure
    - Sufferers fromsystic fibrosis produce thick mucus which blocks bronchioles
    - It arises as a mutation
    - It is inherited as an recessive allele

Comments

Report Tue 18th February, 2014 @ 12:59

This mind map has a good use of colour to separate the key themes. Be creative and add some images to the downloaded mind map to make it even more memorable.