Autumn Foliage Click on image for full size (55K jpeg) Image courtesy of Corel Photography

In the process known as "photosynthesis ", plants use the energy of the Sun to convert water and carbon dioxide into food (sugars) and oxygen. This single chemical reaction provides virtually all the oxygen in Earth's atmosphere and nearly all the food required by living things. Although some protists andIt is a complex chemical process by which plants and other autotrophs create the energy needed for biological life. bacteria are capable of performing photosynthesis, plants are responsible for most of the photosynthesis done on Earth.

The ancestors of modern plants evolved in the seas nearly 700 million years ago. Another 265 million years passed before the first plants appeared on land. These early land plants looked very different than the plants you're familiar with today. In fact, many of them lacked true roots, stems, and leaves - the very structures we tend to associate with plants in general! Since then, plants have taken on a variety of forms and are found in most places on Earth.