1. Blade

The leaf is composed of epidermis, mesophyll and vein. Leaf is an important organ for plants to produce nutrients and an important place for photosynthesis and respiration. The essence of photosynthesis is a process in which green plants use light energy through chloroplasts to synthesize carbon dioxide and water into organic matter and release oxygen. Respiration is a process in which plants absorb oxygen, decompose organic matter into carbon dioxide and water, and release the energy needed for plant growth

2. Petiole

The petiole is the part connecting the leaf and stem. Its upper end is connected with the leaf and the lower end is connected with the stem. The petiole is very small, but its function is very powerful. The main function of petiole is to transport and support. There are vascular bundles inside the petiole, which is the main channel for water and nutrient transport between stems and leaves. Moon cakes are generally cylindrical or slightly flat

3. Stipule

Stipules are placed at the junction of petiole and stem, respectively on both sides. Their morphology and function vary according to different plants. For example, the stipules of pea can carry out photosynthesis, while the stipules of wild jujube can become thorns, and the stipules of more plants will fall off in the process of growth