Find the genotype and phenotype of?

Question

In tomatoes, red fruit color is dominant to yellow. Suppose a tomato plant homozygous for red is crossed with one homozygous for yellow. Determine the genotype and phenotype of a) F1; b) F2 ; c) the offspring of a cross of F1 back to red parent ; d) the offspring of cross of F1 back to yellow parent

Answer 1

When a red 'parent' (RR) is crossed with a yellow 'parent' (rr), all the F1 generation will be heterozygous, Rr, and red colored.
b. If the F1 generation is crossed, you will get red and yellow offspring (F2) in a 3:1 ratio.
c. If the F1 Rr is crossed with the red parental generation (RR), all the offspring would be red.
d. If the F1 Rr is crossed with a yellow parental generation (rr), there would be red and yellow offspring in a 1:1 ratio.

Answer 2

Ok Here you go...

If Red is dominant to Yellow, then the Alelles are R for red and r for yellow. So if an RR were crossed with an rr, all of the offspring would be Rr, red.

To get F2 you would cross two of those offspring, and the results are as follows... 1RR, 2Rr, 1rr, classic ratio, 3 red, 1 yellow

Cross an F1 with the red parent and you get all reds, 2RR, 2Rr
Cross an F1 with the yellow parent and you get 2Rr red, and 2 rr yellow.

Good luck on your homework!

Answer 3

A) Heterozygous red
B) Heterozygous red
C) New F1- Homozygous red, F2- Homozygous red, F3- Heterozygous red, F4- Homozygous yellow
D) 3/4 are Heterozygous red, and 1/4 is yellow

Answer 4

a.)Genotype of F1: all Rr
Phenotype of F1: all red

b.) Genotype of F2: (Rr x Rr) RR:Rr:rr in a 1:2:1 ratio (or 25%:50%:25%)
Phenotype of F2: red:yellow in a 3:1 ratio (or 75% red, 25% yellow)

c.) Genotype of RR x Rr (F1): RR:Rr in 1:1 ratio
Phenotype: all red

d.) Genotype of rr x Rr (F1): Rr:rr in 1:1 ratio
Phenotype: red:yellow in 1:1 ratio