A blue fowl obtained from mating between black and white fowls, is self-crossed. The `F_(2)` ratio is

Options

A. 1 black : 2 white : 1 blue
B. 2 black : 1 white : 1 blue
C. 1 black : 2 blue : 1 white
D. None of the above

Answer

To solve the problem of determining the F2 ratio from the self-cross of a blue fowl obtained from the mating of black and white fowls, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Parental Colors and Genotypes:**
- Black fowl can be represented as BB (homozygous dominant).
- White fowl can be represented as WW (homozygous recessive).

2. **Determine the F1 Generation:**
- When a black fowl (BB) is crossed with a white fowl (WW), all offspring (F1) will be heterozygous (BW), which exhibit a blue color due to incomplete dominance.

3. **Self-Cross the F1 Generation:**
- Now, we self-cross the blue fowl (BW x BW).
- The gametes produced by each BW fowl will be B and W.

4. **Create a Punnett Square:**
- Set up a Punnett square to determine the genotypes of the F2 generation:
```
B W
----------------
B | BB | BW |
----------------
W | BW | WW |
----------------
```

5. **Analyze the Results:**
- From the Punnett square, we can see the following genotypes:
- 1 BB (Black)
- 2 BW (Blue)
- 1 WW (White)

6. **Determine the Phenotypic Ratio:**
- The phenotypic ratio from the self-cross is:
- 1 Black : 2 Blue : 1 White

### Final Answer:
The F2 ratio is 1 Black : 2 Blue : 1 White.

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