A pure tall plant is reared in a soil poor in nutrition and reaches the size of dwarf plant. If this plant is selfed, the phenotype in the `F_(1)` generation is most likely to be

Options

A. All tall plant
B. 50% tall and 50% dwarf
C. All dwarf
D. Data insufficient

Answer

To solve the question regarding the phenotype of the F1 generation when a pure tall plant is selfed after being grown in poor soil conditions, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Genetics of the Parent Plant**:
- The plant in question is a pure tall plant. This means it has a genotype that is homozygous for the tall trait (TT).

2. **Recognize the Effect of Environmental Factors**:
- The plant is grown in poor soil, which affects its growth and results in a size similar to that of a dwarf plant. However, it is important to note that environmental factors like soil nutrition can influence the phenotype (physical appearance) of the plant but do not alter its genetic makeup.

3. **Self-Pollination of the Parent Plant**:
- When this pure tall plant (TT) is selfed, it will produce gametes that are all T (tall allele).

4. **Determine the Genotype of the Offspring**:
- Since both gametes from the self-pollination are T, all offspring will inherit the tall allele from both parents. Therefore, the genotype of the F1 generation will be TT.

5. **Phenotype of the F1 Generation**:
- The phenotype of the F1 generation will be determined by the genotype. Since all the offspring are TT, they will all express the tall phenotype regardless of the environmental conditions they were grown in.

6. **Conclusion**:
- Therefore, the phenotype in the F1 generation is most likely to be all tall plants.

### Final Answer:
The phenotype in the F1 generation is most likely to be **all tall plants**.

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