A fruit is the mature ovary of a seed plant, usually developed from a flower. Fruits have seeds so they further the reproductive cycle. A vegetable is a plant or that part of a plant which is edible, and does not necessarily have a role in the plant's reproductive cycle. fruit is the mature ovary of a seed plant, usually developed from a flower. Fruits have seeds so they further the reproductive cycle. A vegetable is a plant or that part of a plant which is edible, and does not necessarily have a role in the plant's reproductive cycle.