Plant pores, also known as STOMATA, are small openings in the epidermis of a plant that allow for the exchange of gases. STOMATA are typically found on the underside of leaves and are composed of two guard cells that open and close to regulate the amount of water vapor and carbon dioxide that enters and exits the plant. The term 'STOMA' is derived from the Greek word for 'MOUTH, ' and the plural form of the word is 'STOMATA.'