The recombinant phenotypic and genotypic ratio in `F_2` obtained from parental cross having genotypes TTRR x ttrr will be

Options

A. `{:("Phenotypic ratio","Genotypic ratio"),(9:3:3:1,1:2:2:4:1:2:1:2:1):}`
B. `{:("Phenotypic ratio","Genotypic ratio"),(3:3,1:2:3):}`
C. `{:("Phenotypic ratio","Genotypic ratio"),(3:1,1:2:1):}`
D. `{:("Phenotypic ratio","Genotypic ratio"),(3:3,1:2:1:2):}`

Answer

To solve the problem of determining the recombinant phenotypic and genotypic ratios in the `F_2` generation obtained from the parental cross of genotypes TTRR x ttrr, we can follow these steps:

### Step 1: Identify the Parental Genotypes
The parental genotypes are:
- TTRR (homozygous dominant for both traits)
- ttrr (homozygous recessive for both traits)

### Step 2: Determine the Gametes Produced by Each Parent
- The gametes produced by TTRR will be: TR
- The gametes produced by ttrr will be: tr

### Step 3: Form the F1 Generation
When we cross the gametes from the two parents:
- F1 genotype will be: TtRr (all offspring will be heterozygous for both traits).

### Step 4: Self-Fertilization of F1 Generation
Now, we perform self-fertilization of the F1 generation (TtRr x TtRr).

### Step 5: Create a Punnett Square for F2 Generation
We will create a Punnett square for the cross TtRr x TtRr. The gametes from each parent will be:
- From the first TtRr: TR, Tr, tR, tr
- From the second TtRr: TR, Tr, tR, tr

### Step 6: Fill in the Punnett Square
The Punnett square will look like this:

| | TR | Tr | tR | tr |
|------|------|------|------|------|
| **TR** | TTRR | TTRr | TtRR | TtRr |
| **Tr** | TTRr | TTrr | TtRr | Ttrr |
| **tR** | TtRR | TtRr | ttRR | ttRr |
| **tr** | TtRr | Ttrr | ttRr | ttrr |

### Step 7: Count the Genotypes and Phenotypes
From the Punnett square, we can count the genotypes:
- TTRR: 1
- TTRr: 2
- TtRR: 2
- TtRr: 4
- TTrr: 1
- Ttrr: 2
- ttRR: 1
- ttRr: 2
- ttrr: 1

Now, we can summarize the counts:
- **Phenotypic Ratio**:
- Dominant for both traits (T_R_): 9 (TTRR, TTRr, TtRR, TtRr)
- Dominant for T and recessive for R (T_rr): 3 (TTrr, Ttrr)
- Recessive for both traits (ttrr): 1

Thus, the phenotypic ratio is **9:3:3:1**.

- **Genotypic Ratio**:
- Homozygous dominant (TTRR): 1
- Heterozygous (TTRr): 2
- Heterozygous (TtRR): 2
- Heterozygous (TtRr): 4
- Homozygous recessive (ttRR): 1
- Heterozygous (ttRr): 2
- Homozygous recessive (ttrr): 1

Thus, the genotypic ratio is **1:2:2:4:1:2:1**.

### Final Answer
- The recombinant phenotypic ratio in F2 is **9:3:3:1**.
- The recombinant genotypic ratio in F2 is **1:2:2:4:1:2:1**.