Guide Questions:
1. What are the phenotypes in F1 generation?
2. What are the genotype of F1 generation?
3. What are the phenotypes in F2 generation?
4. What are the genotypes of F2 generations?
5. What is the Phenotypic ratio and genotypic ratio of F2 generation?
Answers & Comments
Answer:
1.the F1 generation all have identical genotypes, heterozygous at the seed color gene, and their phenotypes are yellow seeds.
2.The offspring of the RRYY x rryy cross, which is called the F1 generation, were all heterozygous plants with round, yellow seeds and the genotype RrYy.
3.F2 showed 4 different phenotypes: the round and yellow traits did not stay linked to each other. Ratios for each trait corresponds to what one would expect from monohybrid crosses.
4.The second filial (F2) generation cross of true breeding parental groups yields a 1:2:1 ratio, where 25% of the time offspring will be homozygous dominant, 50% of the time, they will be heterozygous, and 25% of the time they will be homozygous recessive.
5.This is a cross between two purebreds, which will produce a F1 generation consisting entirely of dihybrids. Only when you allow the F1 generation offspring to self-pollinate will you perform a dihybrid cross. The resulting F2 generation will have a phenotypic ratio of 9:3:3:1.