Short answers, pulled from the story.
In botany, a fruit is the seed-bearing structure of flowering plants, the angiosperms, formed from the ovary after flowering. This definition includes nuts, bean pods, corn kernels, tomatoes, and wheat grains, which are not commonly called fruit in everyday language.
A tomato is botanically classified as a fruit and a berry because it is a ripened ovary containing seeds. In culinary terms it is regarded as a vegetable because it tastes savory rather than sweet.
No, a strawberry is not a berry. It is classified as a dry aggregate-accessory fruit, meaning its fleshy part comes from the receptacle rather than the ovaries, and the specks on its surface are dry achenes, each an ovary with a seed inside.
A fruit forms through double fertilization, in which pollen reaches the stigma and a pollen tube delivers two sperm to the ovule. One sperm forms the zygote that becomes the embryo, the other forms the endosperm, and the ovary wall ripens into the fruit.
The three main groups are simple fruits, aggregate fruits, and multiple or composite fruits. Simple fruits come from one ovary in a single flower, aggregate fruits from a single flower with many pistils, and multiple fruits from a cluster of flowers.
Fruits disperse seeds by wind, water, explosive dehiscence, and interactions with animals. Hooked burrs cling to animals, parachutes and wings ride the wind, coconuts float across the ocean, and the sandbox tree can fling seeds perhaps up to 100 meters.
Nonfood uses include bayberry wax for candles, opium poppy fruit as the source of codeine and morphine, Osage orange fruits to repel cockroaches, the Luffa fruit's core as a sponge, and pumpkins carved into Jack-o'-lanterns for Halloween.