Here's why:
* Openings: The openings on the underside of a leaf are called stomata (singular: stoma).
* Function: Stomata allow for gas exchange (taking in carbon dioxide for photosynthesis and releasing oxygen as a byproduct). They also help regulate water loss through transpiration.
* Control: Guard cells are specialized cells that surround each stoma. They can change shape to open or close the stoma, regulating the exchange of gases and water vapor.
Let me know if you have any other questions about plant biology!
