Mendel observed that all the `F_(1)` progeny plants.

Options

A. remembled either one of the parents
B. resembled neither of the parents
C. resmbled both of the parents
D. show `3:1` ratio

Answer

**Step-by-Step Solution:**

1. **Understanding Mendelian Genetics**: Mendel's experiments with pea plants led to the formulation of the laws of inheritance. He observed traits such as height (tall vs. dwarf) and how they were passed from one generation to the next.

2. **Identifying the Parental Generation**: In a typical Mendelian cross, consider two purebred plants: one tall (TT) and one dwarf (tt). The tall plant has the genotype TT (homozygous dominant), and the dwarf plant has the genotype tt (homozygous recessive).

3. **F1 Generation**: When these two plants are crossed (TT x tt), all the offspring (F1 generation) will have the genotype Tt. Since T (tall) is dominant over t (dwarf), all F1 progeny will exhibit the tall phenotype.

4. **Analyzing the Options**: The question presents several options regarding the appearance of the F1 progeny:
- Option 1: Resembled either one of the two parents.
- Option 2: Neither of the two parents.
- Option 3: Resembled both of the parents.
- Option 4: Show a 3:1 ratio.

5. **Evaluating Each Option**:
- **Option 1**: Correct. The F1 progeny resemble the dominant parent (tall) because they all have the genotype Tt.
- **Option 2**: Incorrect. The F1 generation does resemble one of the parents (the tall parent).
- **Option 3**: Incorrect. The F1 generation cannot resemble both parents since they all exhibit the dominant trait.
- **Option 4**: Incorrect. The 3:1 ratio applies to the F2 generation, not the F1 generation.

6. **Conclusion**: Based on the analysis, the correct answer is that all F1 progeny plants resemble either one of the two parents, specifically the dominant parent.

**Final Answer**: The correct option is that all F1 progeny plants resemble either one of the two parents.

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