Final answer:
The frequency of the dominant allele is 0.3, and the combined frequency of all other alleles of this gene is 0.7, given that the frequency of the homozygous dominant genotype is 0.09 in a population abiding by Hardy-Weinberg equilibrium.
Step-by-step explanation:
If the frequency of a homozygous dominant genotype (AA) in a randomly mating population is 0.09, we can determine the frequency of the dominant allele A (p). Using the Hardy-Weinberg principle, we know that the frequency of the homozygous dominant genotype is equal to p2. Therefore, in this case p2 = 0.09, and by taking the square root, we find that p = 0.3.
The frequency of the dominant allele is then 0.3. To find the frequency of all other alleles (in this case, just the recessive allele a), we use the fact that the sum of the frequencies of all alleles for a gene is 1 (p + q = 1). Thus, the frequency of the recessive allele a (q) is 1 - p, which is 1 - 0.3 = 0.7. The combined frequency of all the other alleles is therefore 0.7.