Why aren't pea plants part hardy Weinberg?

Answer 1

because . Hardy-Weinberg equilibrium assumes those frequencies will not change from one generation to the next. To show that mathematically, we need to count the alleles in each generation. For instance, we can start by saying that if q = 0.1, then the green pea plants, who have two copies of y, have a genotype frequency of q^2 = 0.01. Likewise the yellow homozygotes have a frequency of p^2 = 0.81. But there's a third type, the heterozygote, that has one copy of each. We can simply subtract the frequencies to see what the proportion of heterozygotes is: 1 - 0.81 - 0.01 = 0.18. Hardy-Weinberg gives us the simple equation to figure out where the alleles are, assuming no evolution: p^2 + 2pq + q^2 = 1. So, 0.18 = 2pq. Why is that? A heterozygote can inherit it's green color y allele from either parent, mom or dad. Because there are two ways to arrive at the probability of a heterozygous state (pq), we need to add those two options together, and pq + pq = 2pq.