external plant parts
roots | stems | buds | leaves | flowers | fruit | seeds
home | introduction | plant life cycles | internal plant parts | external plant parts | plant growth & development
environmental factors affecting growth | plants in communities | plant hormones & growth regulators
Fruit
Structure
Fruit consists of fertilized, mature ovules (seeds) plus the ovary wall, which may be fleshy, as in an apple, or dry and hard, as in an acorn. In some fruits, the seeds are enclosed within the ovary (e.g., apples, peaches, oranges, squash, and cucumbers). In others, seeds are situated on the outside of fruit tissue (e.g., corn and strawberries).
The only part(s) of the fruit that contain genes from both the male and female flowers are the seed(s). The rest of the fruit arises from the maternal plant and is genetically identical to it.
Types of fruit
Fruits are classified as simple, aggregate, or multiple (Figure 21). Simple fruits develop from a single ovary. They include fleshy fruits such as cherries and peaches (drupe), pears and apples (pome), and tomatoes (berries). Although generally referred to as a vegetable, tomatoes technically are a fruit because they develop from a flower. Squash, cucumbers, and eggplants also develop from a single ovary and are classified botanically as fruits.
Other types of simple fruit are dry. Their wall is either papery or leathery and hard, as opposed to the fleshy examples just mentioned. Examples are peanuts (legume), poppies (capsule), maples (samara), and walnuts (nut).
An aggregate fruit develops from a single flower with many ovaries. Examples are strawberries, raspberries, and blackberries. The flower is a simple flower with one corolla, one calyx, and one stem, but it has many pistils or ovaries. Each ovary is fertilized separately. If some ovules are not pollinated successfully, the fruit will be misshapen.
Multiple fruits are derived from a tight cluster of separate, independent flowers borne on a single structure. Each flower has its own calyx and corolla. Pineapples and figs are examples.
additional resources
key for fruit types ...
http://arnica.csustan.edu/key/key2.html
fruit types ...
http://csdl.tamu.edu/FLORA/tfplab/reproch.htm#basic/fruittypes
