Here's how they work:
* Structure: Guard cells are specialized cells that surround small openings called stomata (singular: stoma) on the surface of a leaf.
* Function: Guard cells can change their shape by taking in or releasing water. This change in shape opens or closes the stomata, regulating the passage of gases.
* Gas Exchange: When the stomata are open, carbon dioxide (CO2) can enter the leaf for photosynthesis, and oxygen (O2) produced during photosynthesis can exit. Water vapor (H2O) can also escape through the stomata, a process called transpiration.
* Regulation: Guard cells are sensitive to environmental factors like light, CO2 concentration, and water availability. They open stomata during the day for photosynthesis and close them at night to conserve water.
Let me know if you'd like to know more about the mechanisms that control stomatal opening and closing!
