a leaf performs photosynthesis / gas exchange & a leaf is a part of a plant & photosynthesis makes food for the plant by converting carbon dioxide, water, and sunlight into carbohydrates ->  the leaf part of a plant makes food by photosynthesis  the leaf part of a plant makes food by photosynthesis & a pine tree is a kind of plant ->  the leaf part of a pine tree makes food by photosynthesis  a needle is a part of a pine tree & a needle is the leaf of a pine tree ->  a needle is the leaf part of a pine tree  the leaf part of a pine tree makes food by photosynthesis & a needle is the leaf part of a pine tree -> the needle of a pine tree makes food for pine trees by photosynthesis