Rice leaf. Light micrograph (LM) of a transverse section through the leaf (pinna) of a rice plant.Rice is the seed of the grass species Oryza sativa. As a cereal grain, domesticated rice is the most widely consumed staple food for over half of the world's human population The spongy mesophyll has air spaces for gas exchange and produces carbohydrates by photosynthesis. The upper and lower cuticle protect the leaf from water, sealing water inside and preventing excess rainwater from entering. The upper and lower epidermis produce the cuticle and protect the leaf from herbivores and parasites. The xylem transports water into the leaf while the phloem begins the sugar transport down to the roots. Large arenchyma (air spaces ) are present. In monocot leaf, both small and large parallel vascular bundles are present. Magnification: x10 at 10 centimetres wide.