All hardwood trees, including all the deciduous trees of the temperate zone and broadleaved evergreen trees of the tropical zone, are angiosperms, although sometimes the flowers are inconspicuous. All herbaceous (nonwoody) plants common to our everyday experience, such as grasses and most garden plants, are flowering plants. Angiosperms are adapted to every type of habitat, including water.
The angiosperms are divided into 2 classes: the monocots (e.g., lily) and the dicots (e.g., buttercup). The monocots are almost always herbaceous, with flower parts in multiple of three, parallel leaf veins, scattered vascular bundles in the stem, and one cotyledon, or seed leaf. The dicots are either woody or herbaceous and have flower part usually in fours and fives, net leaf veins, vascular bundles arranged in a circle within the stem, and two
||cotyledons, or seed leaves. Figure 25 compares the characteristics of these two classes. The reproductive cycle of the flowering plant is illustrated in Figure 10-32. The seeds are enclosed by fruit for protection. Many so-called vegetables are actually fruits, e.g., tomatoes, beans, and squash. Nuts, berries, and grains of wheat, rice, and oats are also fruits.|