what is a plant

Plants are amazing organisms. Just like animals, plants are alive. It might look as if plants do nothing at all, but plants show all the characteristics of life, even movement. Plants do not show locomotion, as they can’t move from place to place. But rooted to their spot they must make sure they survive, by competing for space and producing new offspring. To do this plants have five basic structures: leaves, a stem, roots, flowers and fruits. Figure 6.1 shows each of these organs.

Plants are not able to move to a different location (locomotion). This makes a huge difference for a plant compared to an animal that can look for shelter or food.

Plants don’t really have different organ systems. All organs are connected in one big system. Plants use their flowers for reproduction: flowers attract insects. The stem holds the plant upright. Food and water are transported through the stem. Leaves are used to produce food for the plant. One of the functions of the roots is to anchor the plant in the soil. And fruits are used to make sure the seeds will be transported to different locations.

Different plants have different life cycles. You have read that some plants have an annual life cycle, like the common bean. Such plants are called annual plants.

Other plants have a life cycle that takes two years. During the first year these plants grow leaves and roots. During the winter the leaves die. In spring the plant grows new leaves as well as flowers. At the end of the second year the seeds develop. Such plants are called biennial plants.