Question

The traits studied in the experiments involving the crossing of pea plants are seed shape and seed color.

-The shape of the seeds can either be round or wrinkled, and the alleles of these traits are represented by R and r respectively. Allele R is dominant.
-The color of the seeds can be yellow(Y) or green (y). The allele for the yellow seeds is dominant.

A dihybrid cross is preformed between the two pea plants of genotype RrYy. Construct the Punnett square for the corss in the table shown.
QUESTION: Explain how the Punnett square can be used to predict the probability that an offspring from such a cross has a given phenotype (for example yellow, wrinkled seed) Explain your answer with reference to Mendel's Law of independent Assortment.

Answer 1

Each trait is passed independently of the other.

Step-by-step explanation:

Answer 2

The shape and color traits of the pea plant follow the mendelian law of independent assortment. The genes are located on different loci of the chromosomes and do not affect each other. The punnett square for the heterogenous traits of both color and shape will have the two shape alleles (Rr) assorting with the two color alleles (Yy). The gametes in the cross will be RY, Ry, rY and ry. The gametes from the two plants will cross over to result in the formation of a combination of 4 different phenotypes in the ratio of 9:3:3:1 (image). Thus from this ratio we can predict that if the crosses are between plants heterozygous for color and shape trait, then 9 will be round and yellow colored seeds.