1 The results of a study of a population is presented in the

1. The results of a study of a population is presented in the following table. The \"-\" indicates that the other allele is unknown

Which of the conclusions listed below is correct?

Parent1 phenotype	Parent 2 phenotype	Ratio and phenotype of offspring
S -	S -	989 S - 53 ss
ss	S -	560 S- 200 ss
ss	ss	700 ss

Result Number of progeny with the different pheno les Tall/purple flowers Tall/white flowers Short/white flowers Short/purple flowers 300 100 300 900 250 300 500 400 100 300 300 900 360 350 375 340

Solution

1. The results of a study of a population is presented in the following table. The \"-\" indicates that the other allele is unknown

A. All of the S - offspring from the S - X S - matings are homozygous - This is wrong.
If S - X S- are homozygous, 989 S - 53 ss this result is not possbible.

B. If the S- offspring of the S - X S - matings were mated to the S - offspring from the S - X ss matings, there would be no ss offspring; all would be S - This is wrong.
The genotype of S- offspring of the S - X S - may be either SS or Ss.
The genotpe of S - offspring from the S - X ss mating would be Ss.

If the cross from SS X Ss there would be no ss offspring,
but if it is from Ss X ss there is a chance of ss offspring.

C. The ratios of the offspring in the S - X S - matings are due to some S - parents being homozygous and some being heterozygous - This is wrong

If some are homozygous dominant these results are 989 S - 53 ss, 560 S- 200 ss are not possible.

D. The ratios of the offspring in the S- X S - matings conform to the expected ratio for a monhybrid cross. This is wrong.
If it is like that The monohybrid ratio ratio should be 782:260 but here it is 989 S - 53 ss.

Please verify the question and let me know.

2. Select which of the following results would most closely conform to a test cross of a dyhybrid plant
The answer is B. Result D because the observed values is almost equal to 1:1:1:1 ratio