Close up of the outer cell surface (epidermis) of a young developing leaf. Clearly visible are the lip-like structures called stomata, which are the microscopic openings or pores responsible for the intake of carbon dioxide from the atmosphere and extrusion of oxygen to the outside of the leaf. Also visible are the irregular-shaped individual epidermis cells, arranged rather like jigsaw pieces. Collectively, the different cell types give the appearance of a rugged ‘leafscape’.