The dwarfness in plants of `F_(2)` generation is

Options

A. Recessive
B. Dominant
C. Co-dominant
D. In-complete dominance

Answer

To solve the question regarding the dwarfness in plants of the F2 generation, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Genetic Cross**:
- We start with a cross between pure tall plants (TT) and pure dwarf plants (tt).

2. **Determine the F1 Generation**:
- When these two pure lines are crossed, all offspring in the F1 generation will be heterozygous (Tt) and exhibit the dominant trait, which is tallness. Therefore, the F1 generation consists entirely of tall plants.

3. **Self-Cross the F1 Generation**:
- Next, we self-cross the F1 generation (Tt x Tt).

4. **Use a Punnett Square**:
- Setting up a Punnett square for the self-cross (Tt x Tt) gives us the following combinations:
- TT (tall)
- Tt (tall)
- Tt (tall)
- tt (dwarf)

5. **Analyze the F2 Generation**:
- From the Punnett square, we can see the phenotypic ratio:
- 3 Tall (TT, Tt, Tt) : 1 Dwarf (tt)
- This indicates that for every 4 plants, 3 will be tall and 1 will be dwarf.

6. **Identify the Nature of Dwarfness**:
- The dwarf trait (tt) is only expressed when the genotype is homozygous recessive. Therefore, dwarfness is a recessive trait.

7. **Conclusion**:
- Based on the analysis, the dwarfness in the F2 generation is a recessive trait.

### Final Answer:
The dwarfness in plants of the F2 generation is **recessive**.