guard cells

Guard cells are specialized cells located on the surface of plant leaves, forming tiny pores called stomata. These cells control the opening and closing of the stomata, regulating gas exchange and water loss. When the plant needs to take in carbon dioxide for photosynthesis, guard cells swell with water and open the stomata. Conversely, they close the pores to conserve water during dry conditions. This ability helps the plant balance its need for carbon dioxide with water conservation, playing a vital role in its health and growth.