Parts of Fruit
Fruit consists of the fertilized and mature ovules, called seeds, and the ovary wall, which may be fleshy, as in the apple, or dry and hard as in a maple fruit. The only parts of the fruit which are genetically representative of both the male and female flowers are the seeds (mature ovules). The rest of the fruit arises from the maternal plant, and is therefore genetically identical to that parent. Some fruits have seeds enclosed within the ovary (apples, peaches, oranges, squash, cucumbers). Others have seeds that are situated on the periphery of fruit tissue (corn, strawberry).
Types of Fruit
Fruits can be classified as simple fruits, aggregate fruits or multiple fruits. Simple fruits are those which develop from a single ovary. These include cherries and peaches (drupe), pears and apples (pome), and tomatoes (berries). Tomatoes are a botanical fruit since they develop from the flower, as do squash, cucumbers, and eggplant. All of these fruits develop from a single ovary. Other types of simple fruit are dry. The fruit wall becomes papery or leathery and hard. Examples are peanut (legumes), poppy (capsule), maple (samara), and walnut (nut).
Aggregate fruits, such as raspberries come from a single flower which has many ovaries. The flower appears as a simple flower with one corolla, one calyx and one stem, but with many pistils or ovaries. The ovaries are fertilized separately and independently. If ovules are not pollinated successfully the fruit will be misshapen and imperfect. Strawberry and blackberry are also aggregate fruits with the addition of an edible, enlarged receptacle. For this reason, they are sometimes termed aggregate-accessory fruits.
Multiple fruits are derived from a tight cluster of separate, independent flowers borne on a single structure. Each flower will have its own calyx and corolla. Examples of multiple fruits are pineapple, fig and the beet seed.