Hibiscus Stigma Functions Analysis

The stigma is the receptive tip of a flower's pistil or carpel. Its main job is related to pollination.

Key Roles of the Stigma

The stigma typically performs the following functions in flowers like the Hibiscus:

• Receiving Pollen Grains: This is the fundamental role; the stigma is where pollen lands.
• Providing a Sticky Surface: Many stigmas secrete a sugary fluid, making them sticky or feathery to trap pollen effectively.
• Facilitating Pollen Tube Growth: Once compatible pollen lands on the stigma, it absorbs moisture and nutrients, initiating germination and the growth of a pollen tube down the style.

Evaluating the Options

We need to identify which option is NOT a function of the stigma:

• Receiving pollen grains: This is a primary function.
• Providing a sticky surface: This characteristic helps the stigma perform its function of catching pollen.
• Facilitating pollen tube growth: The stigma provides the necessary surface and nutrients for pollen germination and the start of pollen tube growth.
• Producing male germ cells: Male germ cells (male gametes) are produced *within* the pollen grain, which is the male microgametophyte. The stigma is part of the female reproductive organ (pistil) and does not produce male cells.

Hibiscus Stigma Conclusion

The stigma's role involves receiving pollen, providing a suitable landing surface (often sticky), and initiating pollen germination. It does not produce the male germ cells; that process occurs inside the pollen grain after it has landed on the stigma.