Question

What will be the number of genotypes and phenotypes in F1, if we crossbreed the plants with Purple Large round flowers (PlLlRr) (trihybrid cross)? Both plants are heterozygous for all three traits and the traits behave in a dominant and recessive pattern.


a. 8 genotypes; 27 phenotypes

b. 81 genotypes; 16 phenotypes

c. 16 genotypes; 64 phenotypes

d. 64 genotypes; 16 phenotypes

e. 27 genotypes; 8 phenotypes

Answer 1

Answer:

e

Explanation:

PpLlRr x PpLlRr

Gamete possibilities:

3 x 3 x 3 = 27 gamete possibilities. This means 27 different genotypes.

Some of these are duplicates, though: We need to see how many phenotypes, so we need to discount the heterozygous. That means there are two possibilities per allele pair, the homodominant and the homorecessive.

2 x 2 x 2 = 8 possibilities. This means 8 different phenotypes.