Final answer:
The thickened ovary wall of a plant may join with other parts of the flower stem to become the fruit, which forms after fertilization to protect the embryo and aid in seed dispersal.
Step-by-step explanation:
The thickened ovary wall of a plant may join with other parts of the flower stem to become the fruit. Flower branches, which are specialized for reproduction and are found in some seed-bearing plants, consist of both male and female organs, or in some cases, just one. The innermost part of the flower, the gynoecium, includes the ovary where the ovules are contained. After fertilization, the ovary wall thickens and develops into the fruit, which protects the embryo and facilitates seed dispersal. The fruit is not necessarily sweet or fleshy, as in the case of vegetables like eggplants, zucchini, and tomatoes, which are technically fruits because they originate from the ovary and contain seeds.