In Red-White flowered cross of Mirabilis jalapa, `F_(2)` generation has red, pink and white flowered plants in the ratio of

Options

A. `1:2:1`
B. `1:0:1`
C. `2:1:1`
D. `1:1:2`

Answer

To solve the question regarding the phenotypic ratio of flower colors in the F2 generation of Mirabilis jalapa, we can follow these steps:

### Step-by-Step Solution:

1. **Identify Parental Generation**:
- We start with a red-flowered plant (homozygous, RR) and a white-flowered plant (homozygous, rr).

2. **Determine the F1 Generation**:
- When we cross the red-flowered plant (RR) with the white-flowered plant (rr), the gametes from the red plant (R) combine with the gametes from the white plant (r).
- This results in all offspring being heterozygous (Rr), which will display the red flower phenotype due to the dominance of the red allele.

3. **Self-Cross the F1 Generation**:
- Now, we take two F1 plants (Rr) and cross them to produce the F2 generation.
- The gametes from each F1 plant can be R or r.

4. **Create a Punnett Square**:
- Set up a Punnett square with the gametes:
```
R | r
---------------
R | RR | Rr
---------------
r | Rr | rr
```
- This results in the following genotypes:
- 1 RR (red)
- 2 Rr (pink)
- 1 rr (white)

5. **Determine the Phenotypic Ratio**:
- From the Punnett square, we can see the phenotypic ratio of the offspring:
- 1 red (RR) : 2 pink (Rr) : 1 white (rr)
- Therefore, the ratio of red to pink to white flowers in the F2 generation is 1:2:1.

### Final Answer:
In the red-white flowered cross of Mirabilis jalapa, the F2 generation has red, pink, and white flowered plants in the ratio of **1:2:1**.

---