In the first step of monohybrid cross experiment, Mendel selected Pea plants which were

Options

A. Pure tall as male and pure dwarf as female
B. Pure tall as female and pure dwarf as male
C. Heterozygous tall as male and pure dwarf as female
D. Heterozygous tall as female and pure dwarf as male.

Answer

**Step-by-Step Solution:**

1. **Understanding the Monohybrid Cross**: Mendel's monohybrid cross involves studying the inheritance of a single trait by crossing two plants with contrasting characteristics.

2. **Selection of Pea Plants**: Mendel selected pea plants (Pisum sativum) that exhibited two contrasting traits for height: tall and dwarf.

3. **Identifying Pure Breeding Lines**: Mendel used pure breeding lines, which means he selected plants that consistently produced offspring with the same trait when self-pollinated.

4. **Crossing the Plants**: In the first step of his experiment, Mendel crossed a pure tall plant with a pure dwarf plant.

5. **Determining the Parental Roles**: In this specific cross, the pure tall plant was designated as the female parent, and the pure dwarf plant was designated as the male parent.

6. **Conclusion**: Therefore, the correct selection for the first step of Mendel's monohybrid cross experiment is that he selected pure tall as female and pure dwarf as male.

**Final Answer**: Pure tall as female and pure dwarf as male (Option B).

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