Adaptations of a leaf for photosynthesis

Adaptations of a leaf for photosynthesis Transverse section of a leaf showing some of the adaptations • Cuticle: - Is non-cellular, water proof and transparent. It allows light to pass through. • Upper epidermis: - Is a single layer of cells on the upper surface of a leaf. It allows light to pass to the cells below. • Palisade mesophyll: - has cells vertically arranged such that many can fit into a small space. The cells have large number of chloroplasts. • Chloroplasts:- contain chlorophyll for absorbing sunlight. • Spongy mesophyll: - Have large air spaces for fast diffusion of gases to and from the photosynthesizing cells. The cells have few chloroplasts. • Veins (Vascular bundles): - They act as drain pipes distributing raw materials to the leaves and conducting away manufactured food to other parts of a plant. • Stoma: - A pore that allows gaseous exchange to take place. Carbon dioxide enters and oxygen leaves the leaf through stomata. • Thin lamina: - Provides a short distance over which diffusion of gases take place. • Broad lamina: - Some leaves have a broad lamina which provides a large surface area for absorbing sunlight energy.