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    Anyone got a decent site to explain it/notes or can help me with it? I'm at a total blank atm (Using the heinmann book)
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    u show the dominant or recessive alleles in both parents genes and the combinations that offsprings could have
    like this
    G g
    g Gg gg
    G GG Gg
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    (Original post by Waqar Y)
    Anyone got a decent site to explain it/notes or can help me with it? I'm at a total blank atm (Using the heinmann book)
    I don't know any sites atm but I'll do my best here. First some definitions:

    Allele -> Alternative version of a gene.
    Genotype -> The alleles that an organism contains (within the DNA).
    Phenotype -> The physical characteristics that can be seen as a result of the genotype.

    Since our normal cells are diploid (two sets of chromosomes) we normally contain two alleles for a specific trait.

    Dominant alleles will have their traits expressed even if only one copy is present, but two copies of a recessive allele is needed for its trait to be expressed.



    The diagram above is a monohybrid cross, which means only one trait is being focused on. This one is about hair colour. A is the allele for normal hair, a is the allele for albino hair. (Capital letters are given to dominant alleles).

    The four combinations show the possibilities of allele combinations, depending on which chromosomes are given to the offspring.

    AA and Aa give normal hair. aa gives albino hair. Since only one copy of A is needed because it is dominant.
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    Thank you
 
 
 
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