Progeny are phenotypically and genotypically similar in

Options

A. `F_(2)` generation
B. `F_(3)` generation
C. `F_(4)` generation
D. `F_(1)` generation

Answer

To determine in which generation the progeny are phenotypically and genotypically similar, we will analyze the options provided: F1, F2, F3, and F4 generations.

### Step-by-Step Solution:

1. **Understanding the Generations**:
- **F1 Generation**: This is the first filial generation, produced by crossing two parental plants (e.g., tall and short). The F1 generation usually exhibits a uniform phenotype (either all tall or all short) if one trait is completely dominant over the other.
- **F2 Generation**: This generation is produced by interbreeding the F1 individuals. The F2 generation shows a mix of phenotypes due to the segregation of alleles.
- **F3 Generation**: This is derived from the F2 generation. The phenotypic and genotypic ratios can vary widely depending on the combinations of alleles.
- **F4 Generation**: This generation is derived from the F3 generation and will also show a variety of phenotypic and genotypic outcomes.

2. **Analyzing the F1 Generation**:
- In the F1 generation, all progeny are phenotypically similar (either all tall or all short) but are not genotypically similar since they are heterozygous (Tt) if one trait is dominant.

3. **Analyzing the F2 Generation**:
- The F2 generation arises from the self-pollination of F1 individuals. Here, we can observe a variety of phenotypes (tall and short plants) and genotypes (TT, Tt, tt). The genotypic ratio is 1:2:1 (TT:Tt:tt), while the phenotypic ratio is 3:1 (tall:short).

4. **Conclusion**:
- The F2 generation is where the phenotypic and genotypic ratios differ. The F1 generation is where the progeny are phenotypically similar (all tall or all short) but not genotypically similar. Therefore, the correct answer is **F1 generation**.

### Final Answer:
The progeny are phenotypically and genotypically similar in the **F1 generation**.