The structure of a leaf is designed to maximize photosynthesis, the process by which plants convert sunlight into energy. A typical leaf consists of several layers, including the epidermis, which protects the leaf, and the mesophyll, where most photosynthesis occurs. The mesophyll contains chloroplasts, which are the organelles that capture sunlight. Leaves also have small openings called stomata that allow for gas exchange, letting carbon dioxide in and oxygen out. The veins in a leaf transport water and nutrients from the plant and help support its structure. Together, these components enable leaves to efficiently perform their vital functions.