圖書序言
Plants
植物
Root
Roots are the part of the plant that is in the ground. The roots of the plant hold the plant in the ground. On each root are tiny root hairs. These tiny root hairs grow into the soil. They take in water and minerals. The plant uses water and minerals to make food. Without water and minerals, the plant cannot grow.
Stems
Now look at a plant’s stems. These stems are like tiny pipes. Water and minerals can travel through the stem. The stem takes water and minerals to the leaves, where the plant’s food is made.
Stems are many different sizes. The big tree trunk is a stem. The stem of a cabbage plant is so short that you may not see it. Vines are a kind of stem. The tiny tubes in the stem of a celery plant are easy to see.
Leaves
The leaves of green plants have tiny openings in them. To see these openings, you will need the help of a microscope.
A microscope makes things look much bigger than they really are.
The tiny openings are important to help the plant grow. Carbon dioxide, a gas from the air, enters the leaf by the openings. Carbon dioxide is given off by people and animals when they breathe.
When plants use carbon dioxide, they give off a gas called oxygen. People and animals need oxygen to live. Some of the water in the plant is given off through the leaves. Carbon dioxide goes into the leaves of the plant through tiny openings like those in this picture.