Question

Opening and closing of stomata is regulated by:

• A. Guard cells
• B. Epidermal cells
• C. Xylem
• D. Phloem

Hint:

Think of guard cells like a pair of balloons. When you "fill" them with water, they curve outward and create a gap (the stoma) in the middle.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Stomata are tiny pores located on the surface of leaves that allow for gas exchange and transpiration. Their opening and closing must be tightly controlled to prevent excessive water loss.
Step 2: Detailed Explanation:
Each stoma is flanked by two kidney-shaped (in dicots) or dumb-bell shaped (in monocots) Guard cells. When water flows into these cells, they swell and become turgid, causing the pore to open. When they lose water, they become flaccid and the pore closes.
Step 3: Final Answer:
The correct option is (a).