Allozyme phenotypes of alcohol dehydrogenase in the flowering plant phox drummondii are determined by three co-dominant alleles of a single gene. in one sample of 70 plants the following data were obtained:

genotype a1a1 a2a2 a3a3 a1a2 a1a3 a2a3
number 4 24 10 10 2 20
what is the frequency of the a2 allele in this sample?

0.628

0.238

0.557

0.432

0.337

0.557

Explanation:

First calculate for the genetic frequencies

A1A1 = 4/70 = 0.057

A2A2 = 24/70 = 0.34

A3A3 = 10/70 = 0.14

A1A2 = 10/70 = 0.14

A1A3 = 2/70 = 0.029

A2A3 = 20/70 = 0.29

Frequency of A2 allele therefore = 0.34 + (0.5×0.14) + (0.5×0.29)

= 0.556

The difference in the answer is due to approximations.

chromosomes carry the genetic information for organisms. also, chromatin is the thread like dna which is located in the nucleus of an organism.