There are over 2 million kinds of living organisms on Earth, and more are being discovered all the time. Scientists divide these things into groups, called kingdoms. This book looks at five groups in the plant kingdom: mosses and liverworts, horsetails, ferns, conifers and flowering plants. Find out about the characteristics, life cycles, and habitats of each group of plants. Discover how plants make food, grow, reproduce and adapt to different habitats. Learn how some plants are threatened with extinction and why we need to make sure that a diversity of plants are protected for the future. This title was previously published by Wayland as Classification: The Plant Kingdom. This edition has been simplified and updated.