How does a plant grow?

Have you been a tree in a school play? Many people have. If you stood there with your arms out you might have thought, "What is it like to be a plant?" The answer would be,

"Very different from being a human". Just think about your body and the body of a plant. If you were a plant in a play, your feet would be the roots, your body would be the stem, your arms and hands would be the leaves and your head would be the flower.

Let us compare your body parts with those of a plant. Your feet are made from bone, flesh and skin. A root does not have bones, flesh and skin but is made from plant material. A large amount of plant material is in the form of fibres. You can see them in the end of a celery stalk after you have taken a bite.

Your feet are short compared to the rest of your body. The root of a plant may be the longest part of its whole body. While each of your feet has five toes on the end, a root forms many branches. They may spread out along the whole length of the root. Each branch may have branches and on the end of them are coats of tiny white hairs. In the middle of the root are large numbers of pipes. They carry water and nourishment up to the stem and food from the leaves down to the root tips.

When we compare your body to a stem we find even more differences. Your body has many different parts inside. These parts do different things. For example, your stomach helps digest your food, your lungs are needed for breathing and your heart pumps blood. A plant stem has none of these parts inside it. It has the same kinds of pipes as the root.

On the outside of your body there are four limbs °© your two arms and two legs. On the outside of a stem there may be many limbs which we call branches. These are best seen in trees. Each branch divides into smaller and smaller branches, which end in twigs.

If you look at your hand you can spread out your fingers and you may think that they look a little like the veins in a leaf. Again the fingers are made of bones, flesh and skin and the leaves are made of cellulose and pipes. The pipes form the veins that you can see in the leaf.

Finally, we have reached your head. If you have not been a tree in a play yet, there is still time for you to be a plant such as a sunflower or a weed. If you take the part, the costume-maker will turn your head into a flower by placing petals round your face. As with all the other parts of the plant, a flower is very different from a head. In a head are the brain, eyes, ears, mouth and teeth. In a flower are parts for attracting insects and for creating fruits and seeds.

Although you and a plant are very different you both have one thing in common. You are both living things. Every living thing can make special actions called life processes. Some examples of life processes are growing, feeding and breeding. Plants and people grow in a similar way by increasing in size but they feed and breed differently. Plants can make their own food, unlike people, and when they breed, they produce offspring inside seeds and fruit.

Next time you are a plant in a play, remember that you are playing the part of a very different form of life.

What does a plant use its root for?

A plant uses its root to hold itself in the ground. In windy weather the leaves and stem are blown about and if the roots did not grip the soil, the whole plant could be blown away. Some large animals, such as deer, feed on plants. As they feed, they tug on the leaves and stem. The root acts again to hold the plant in place. You can think of a root holding a plant in place on the ground like an anchor holding a ship in place on the sea. The root also takes in water and nourishment from the soil for the plant to use.

What is the purpose of a stem?

It has a number of purposes. It holds up the leaves to the light so they can make food. It holds the flowers up into the air so that the plant can breed. It contains pipes for carrying water and nourishment from the root to the leaves and for carrying food from the leaves to the flowers and the root.

What does a plant use its leaves for?

It uses its leaves to make food. The leaves need air, sunlight, water and nourishment to make food. On the underside of leaves are tiny holes, which can only be seen with a microscope. They let in air. The sunlight is trapped in the green substance in the leaves and the water and nourishment pass into the leaf in the pipes, which make the leaf veins.

What is the purpose of a flower?

The flower is the part of the plant that produces offspring. This process is called breeding or reproducing. A yellow dust, called pollen, plays an important part in the breeding of plants. It must pass from one flower to another so that breeding can take place. The pollen moves in one of two ways. It is carried by insects or it is blown by the wind. Plants, which use pollen carried by insects, have flowers with large brightly coloured petals, which may have a strong scent. These features of the flower attract the insects carrying pollen. When the insects arrive at the flower, they feed on nectar that the flower has produced and leave their pollen behind when they fly away. Flowers, which use pollen carried by the wind, do not have brightly coloured petals, scent and nectar. They have tiny sticky brushes to catch the pollen as it passes by. Once a flower has captured its pollen it makes fruits and seeds.

What is the difference between a fruit and seed?

A seed is a container for a tiny plant called the offspring and its store of food. A fruit is a container for one or more seeds. Some fruits are juicy like apples or oranges. Other fruits may be dry and papery like the winged fruits of the sycamore tree.

Do all plants have flowers?

No. Mosses and ferns produce spores to breed. A spore is a very tiny case, which contains a piece of the moss or fern plant. When the spore lands in a suitable place it breaks open and a new plant begins to grow. Conifers do not produce flowers. They produce cones. One kind of cone produces pollen and another kind of cone produces seeds. The plants, which produce flowers, are called flowering plants.