foreign [Music] stomata play a critical role by regulating the exchange of gases particularly carbon dioxide and oxygen between the plant and its environment stomata are tiny openings found mostly on the underside of the leaves the stomata can be opened and closed by specialized cells called guard cells these cells are shaped like Crescent moons or sausages and there are two of them for each stomatal pore thank you when stomata are open they allow carbon dioxide to enter the leaf which is then used by the plant to produce glucose food through photosynthesis [Music] at the same time oxygen a byproduct of photosynthesis is released through the stomata into the atmosphere at night when sunlight is not available the rate of photosynthesis significantly decreases and the need for CO2 intake is greatly reduced closing the stomata at night helps to conserve water by reducing transpiration which is the loss of water vapor this is particularly important in arid environments where water conservation is essential for plant survival when the Sun rises guard cells open the stomata and photosynthesis continues [Music] worksheets relating to this short video can be downloaded by creating a free account at ngscience.com don't forget to subscribe to the NG science YouTube channel to never miss a video