33 L4-All About Plants

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Oxford Read and Discover level 4 All About Plants by Julie Penn

Introduction Plants are very important. We need them for food, wood, medicines, and many other things. We see plants all around us— in fields, parks, gardens, and even in our homes. What plants do you know? What plants grow in your country? Where do the plants grow? Discover! Now read and discover more about amazing plants!

Chapter 1 Plants in Our World Plants are living things. They feed, breathe, grow, and make new plants, but they are different from animals. Plants don't move from place to place like animals do. Plants keep growing, but animals don't grow when they are older. Scientists don't know how many plants there are, but they think that there are more than 300,000 types! Many of these plants grow in rainforests. Scientists think that there are thousands more plants that we don't know about yet. There were plants on Earth more than two billion years ago! The first plants didn't grow on land— they grew in water. It took hundreds of millions of years for plants to change and to grow on land. Before plants, animals did not live on Earth. There was no oxygen in the air, and animals need to breathe oxygen. Plants produced oxygen and food for animals. They made life possible for us! Discover! Plants started to grow on land more than 400 million years ago. This is a fossil of one of the first land plants.

Chapter 2 Different Plants There are many different types of plant. Scientists put plants into different groups. They think about how plants grow and how they make new plants. Most plants make seeds. These plants are called seed plants. New plants grow from the seeds. Many seed plants produce flowers. These plants are called flowering plants. Most of the plants that you see around you are flowering plants. How many flowering plants do you know? Some seed plants produce cones, not flowers. These plants are called conifers. Some of the world's tallest trees are conifers. Discover! The biggest cones can be 40 centimeters long and they can weigh 4 kilograms! Plants that don't make seeds are called non-seed plants. Ferns and mosses are non-seed plants. They don't make seeds, but they make tiny spores. New plants grow from these spores.

Chapter 3 Plant Parts A flowering plant has four main parts leaves, stems, roots, and flowers. The roots hold the plant in the soil. They take water and minerals from the soil. The leaves make food for the plant. The stems take water from the roots to the leaves. They also take food from the leaves to other parts of the plant. The stems support the plant, too. The flowers make seeds, and new plants grow from these seeds. Different vegetables come from different parts of a plant. Potatoes are from the roots of a plant. Asparagus is the stem. Cabbages are leaves. Broccoli is the flower. Food like apples and oranges are fruits. Fruits grow from flowers, and the plant's seeds are in the fruit. Discover! The biggest seeds are from the coco de mer plant. They can weigh 30 kilograms —that's about the same as a child who is ten years old!