Question

Which one of the following types of pollination brings genetically different types of pollen grains to the stigma?

• A. Cleistogamy
• B. Autogamy
• C. Geitonogamy
• D. Xenogamy

Hint:

Xenogamy = X-tra (Different) plant. It is the only one that truly achieves "Cross-Pollination" in a genetic sense!

Answer 1

The Correct Option is D

Step 1 : Understanding the Question
Identify the type of pollination that involves a different genetic source.
Step 2 : Key Formulas and approach
$\text{Same flower} \rightarrow \text{Autogamy}$. $\text{Same plant} \rightarrow \text{Geitonogamy}$. $\text{Different plant} \rightarrow \text{Xenogamy}$.
Step 3 : Detailed Explanation

Autogamy (A): Self-pollination within (A) one flower. No variation.

Cleistogamy (D): Pollination in (B) closed flowers. No variation.

Geitonogamy (C): Functionally cross-pollination but (C) genetically selfing as it's on the same plant.

Xenogamy (B): Pollen comes from a (D) different plant, ensuring genetic variation.

Step 4 : Final Answer
Xenogamy is the correct answer (B).