In this topic you will learn about different kinds of seed plants.

Vascular plants reproduce from seeds. A seed is an undeveloped plant with stored food, sealed in a protective covering. Most of the plants you see every day are seed plants. They include grasses, trees, shrubs, and bushes. They all have roots, stems, and leaves.

There are two major groups of seed plants. Some plants are called angiosperms. An angiosperm is a seed plant that produces flowers. The others are called gymnosperms. A gymnosperm is a seed plant that does not produce flowers.

The gymnosperms are the oldest seed plants. The gymnosperms are divided into four divisions. They are the conifers, cycads, gingkoes, and gnetophytes. A conifer is a gymnosperm that produces seeds in cones and has needlelike leaves. The seeds are produced on the scales of the female cones. Fruit does not surround the seeds. The leaves of most gymnosperms look like needles or scales.

Most gymnosperms are evergreens. Evergreens lose only a few leaves at a time and constantly replace the leaves they have lost. Some conifers, such as the larch, dawn redwood, and bald cypress, are called "deciduous" trees, meaning that they shed their leaves each fall.

Angiosperms are the best-adapted division of seed plants. There are about 235,000 different kinds of angiosperms, and they live in all climates and in all parts of the world. It is easy to distinguish an angiosperm from a gymnosperm. Angiosperms produce flowers, while gymnosperms do not. The seeds of angiosperms are inside a fruit. Gymnosperms do not produce fruit.

Scientists divide the angiosperms into two classes based on a particular characteristic. That characteristic is the number of cotyledons. A cotyledon is a tiny leaflike structure inside a seed of an angiosperm. Some angiosperm seeds contain only one cotyledon in each seed and are called monocots. Corn, rice, and wheat are examples of monocots. Angiosperms with two cotyledons in each seed are called dicots. Bean plants, maple trees, rose plants, and cactuses are some of the dicots.

The aroma of a flower attracts an insect, which helps with the process of pollination for the plant.

Almost all the food you eat that comes from a plant is produced by a flowering plant. Some produce chemicals that are used in cosmetics and perfumes. Others, such as plants used as spices, flavor the foods you eat.