EnviroKids January 2019 Issue

Structure of Plants Plants and trees are a source of oxygen, and are also a source of food and shelter for every li ving thing on Earth. But how do they grow?

Although there are so many different types of plants and flowers, they all have certain things in common. All plants have roots, stems and leaves. They all need soil, sun and water to grow, and they all produce their own energy (food) through the process of photosynthesis. Almost all plants start out as a seed. When a seed is in a healthy environ- ment (enough sun, water and miner- als from soil), it can begin to grow. Water coats the seed and softens it to allow it to sprout. The soil releases nutrients into the seed that encour- ages this growth further. The first parts to pop out of a seed are the cotyledon (first leaves) and the radicle (root). The root grows downwards into the soil and con- tinues to absorb nutrients, while the cotyledon grows upwards and remains the main source of food for the seed. The next part of the plant to grow is the stem, which is also called the hypocotyl. Then comes the epicotyl, which are the first “proper” leaves to grow. When these pop up, the plant is already above the ground and the cotyledon start to die off.

As the leaves and stem continue to grow, so do the roots. The roots are divided into the main root (first to come out of the seed), and the lateral roots (those that break away from the main root). Buds grow on the stem of a plant, which grow into petioles (smaller stems or branches). The leaves are the part of the plant that produce energy (food). They use sunlight, water, and carbon dioxide to make glucose for the plant. As long as conditions remain favourable, a plant or tree will continue to grow and produce oxygen for us.

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