In one generation, the frequency of the a allele is 70 percent and the frequency of the a allele is 30 percent. what are the chances of an individual in the next generation having the genotype aa if the population is in genetic equilibrium?

49%
42%
30%
9%

p - the frequency of the A allele.
q - the frequency of the a allele.

p² - the frequency of dominant homozygote (with AA genotype)

2pq - the frequency of heterozygote (with Aa genotype)

q² - the frequency of recessive homozygote (with aa genotype)

We know:

p = 70% = 70/100 = 0.7

q = 30% = 30/100 = 0.3

We need to calculate the frequency of the genotype aa:

q² = ?

Since we know the frequency of allele q, it is easy to calculate the frequency of the genotype aa:

q² = 0.3² = 0.09 = 0.09 · 100% = 9%

the solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. this process is called passive transport or facilitated diffusion, and does not require energy.