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    Colour is controlled by a single gene with twoalleles. The allele for black, B, is dominant to the allele for red, b.

    Some of the results from the investigation are shown in the table.

    Year Season Frequency of b allele
    1933 Autumn 0.70
    1934 Spring 0.82
    1934 Autumn 0.59
    1935 Spring 0.76
    1935 Autumn 0.57
    1936 Spring 0.78

    (b) Use the Hardy-Weinberg expression to estimate the percentages of red ladybirds and black lady birds in the Autumn 1933 ladybird population.
    Show your working.


    Mark scheme:
    Two marks for correct answer of 49% red and 51% black;
    One mark for incorrect answer in which p/frequency of black allele/B is
    Identified as 0.3 and q/frequency of black allele/B as 0.7;

    Ive got up to finding 0.3=p and 0.7=q but am stuck with what to do after
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    (Original post by Lollypop0)
    Some of the results from the investigation are shown in the table.

    Year Season Frequency of b allele
    1933 Autumn 0.70
    1934 Spring 0.82
    1934 Autumn 0.59
    1935 Spring 0.76
    1935 Autumn 0.57
    1936 Spring 0.78

    (b) Use the Hardy-Weinberg expression to estimate the percentages of red ladybirds and black lady birds in the Autumn 1933 ladybird population.
    Show your working.


    Mark scheme:
    Two marks for correct answer of 49% red and 51% black;
    One mark for incorrect answer in which p/frequency of black allele/B is
    Identified as 0.3 and q/frequency of black allele/B as 0.7;

    Ive got up to finding 0.3=p and 0.7=q but am stuck with what to do after
    You have not posted the full info to use Hardy-Weinburg e.g. the allele for red and also black ladybird (e.g. whether its homozygous recessive or not)
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    Hopefully added all info required now
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    you do q squared, which is 0.49 (or 49%), then 100-49=51%

    (Original post by Lollypop0)
    Colour is controlled by a single gene with twoalleles. The allele for black, B, is dominant to the allele for red, b.

    Some of the results from the investigation are shown in the table.

    Year Season Frequency of b allele
    1933 Autumn 0.70
    1934 Spring 0.82
    1934 Autumn 0.59
    1935 Spring 0.76
    1935 Autumn 0.57
    1936 Spring 0.78

    (b) Use the Hardy-Weinberg expression to estimate the percentages of red ladybirds and black lady birds in the Autumn 1933 ladybird population.
    Show your working.


    Mark scheme:
    Two marks for correct answer of 49% red and 51% black;
    One mark for incorrect answer in which p/frequency of black allele/B is
    Identified as 0.3 and q/frequency of black allele/B as 0.7;

    Ive got up to finding 0.3=p and 0.7=q but am stuck with what to do after
 
 
 
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