Question

Question #9b514

Answer 1

See below.

Explanation:

Hardy Weinberg principle states that allele frequencies in a population are stable and is consistent from generation to generation.

Sum total of all the allelic frequencies is 1. In a diploid cell, `p` and `q` represent the frequency of allele A and a.

The frequency of AA individuals is simply `p^2`.

Similarly of aa is `q^2`, of Aa is `2pq`.

Hence `p^2 + q^2 + 2pq = 1`.

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1] Allele frequency of R is 20%.
Which means `p = (20/100) = 0.2`

Now, `p + q = 1`
`q = 0.8`

The frequency of RR, i.e `p^2 = (0.2)^2 = 0.04`.

The frequency of rr, i.e `q^2 = (0.8)^2 = 0.64`.

The frequency of Rr, i.e `2pq = (2)(0.2)(0.8) = 0.32`

2] Total number of individuals `= 400`
Number of homozygous recessive individuals `= 9`

Frequency of homozygous individuals i.e, `q^2 = (9/400) = 0.0225`.

Frequency of the allele `q = sqrt(0.0225) = 0.15`

Frequency of `p = 1 - q = 0.85`

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I answered two of them. Try the others as I've told you the concept. If you get stuck on any of them let me know.