What is the phenotype ratio for TTyy X TtYy?

Is it 8:8 for tall + yellow to tall + green?

How is that?

I got 4 Ttyy, 4 TtYy, 4 TTYy, and 4 TTyy.

Ttyy an TTyy are both tall+green, and TtYy and TTYy are both yellow.

Right, all are tall and half are yellow.

To determine the phenotype ratio, we need to understand how alleles are inherited and how they interact. In this case, we are dealing with two traits: height (tall or short) and color (yellow or green). Each trait is controlled by two alleles, where "T" represents the dominant allele for tall height, "t" represents the recessive allele for short height, "Y" represents the dominant allele for yellow color, and "y" represents the recessive allele for green color.

First, let's consider the genotype of each parent:
- The first parent is TTyy, which means it has two dominant alleles for height (T) and two recessive alleles for color (y).
- The second parent is TtYy, which means it has one dominant allele and one recessive allele for both height (Tt) and color (Yy).

To determine the possible genotype combinations and subsequently the phenotype ratio of their offspring, we can use a Punnett square. A Punnett square shows all possible combinations of alleles from both parents and predicts the genotypic and phenotypic outcomes.

The Punnett square for this cross would look like:

T T y y
---------------------------------
T | TT TT Ty Ty
t | Tt Tt ty ty

In this case, we find that there are four possible combinations of alleles in the offspring: TT, Tt, Ty, and ty. Let's now determine the phenotype for each combination:

- TT: Tall height and yellow color
- Tt: Tall height and yellow color
- Ty: Tall height and green color
- ty: Short height and green color

From the Punnett square, we can see that there are 2 out of 4 combinations that result in tall and yellow phenotypes. Therefore, the phenotype ratio is 2:4 (or simplified as 1:2) for tall and yellow to all possible phenotypes.

If green is yy, then it is 12 tall+yellow and 4 tall+green