Question

Answers for the letter b, c, and d.a. Show the f2 generation Punnett square, when two offspring from the f1 generation cross. b. What is the phenotypic ratio for the outcome above? Put full phenotype descriptions with the ratio. c. This ratio is regarded as the key clue which led Mendel to discover which law? d. From the ratio, how many homozygous pure-breed offspring were there eventually after the final cross? Give the genotypes of all.

Answer 1

B. Phenotypic ratio outcome

9- Yellow round (IIRR, IIRr, IiRR, IiRr, IIRr, IiRr, IiRR, IiRr, IiRr)

3- Yellow wrinkled (IIrr, Iirr, Iirr)

3- Green round (iiRR, iiRr, iiRr)

1- Green wrinkled (iirr)

The ratio is 9:3:3:1

C. This ratio is regarded as the key clue which led Mendel to discover the LAW OF INDEPENDENT ASSORTMENT.

The law of independent assortment states that the alleles of two or more different genes are sorted into gametes that are independent of one another.

D. There were two homozygous pure-breed offspring during the final cross. These are:

IIRR - homozygous yellow round

iirr- homozygous green wrinkled