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Genetics and evolution

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Question 36

The Hardy-Weinberg principle can be used to calculate allele and genotype frequencies in populations.

A population of a wildflower species, Mimulus guttatus, has two distinct flower colours, red and yellow, which are determined by a single gene with two alleles.

The allele coding for red flowers, R\text{R}R, is dominant to the allele coding for yellow flowers, r\text{r}r.

A meadow was found to contain 800 M. guttatus plants, 128 of which had yellow flowers.

Using the Hardy-Weinberg principle, calculate the number of plants in this meadow that are expected to have a homozygous dominant (RR\text{RR}RR) genotype.

Use the equations:

p+q=1 p + q = 1 p+q=1 p2+2pq+q2=1 p^2 + 2pq + q^2 = 1 p2+2pq+q2=1
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Genetics and evolution Questions

  1. A Level
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  3. /Genetics and evolution