Holt General Science [antikvár]

To The Student: this book is about the exploration of the world around you. Scientists are explorers who seek the answers to such questions as: What is matter made of? What makes a plant or animal alive? What is the nature of light, electricity, and magnetism? How are human activities affecting other living things in the environment? What is the structure of the inside of our earth? In this book you will find out how scientists in the past tried to find the answers to such questions and how scientists today continue to seek answers to their questions. Holt General Science is divided into four units. Each unit explores a different branch of science: chemistry, physics, earth science, and biology. Each unit is divided into chapters. In the first chapter, "What Does a Scientist Do?," you will learn about some of the skills that scientists use to solve problems. These are skills that you will use as you continue to study science. The rest of Unit 1 is about chemistry, the study of matter. You will find out what scientists in the past discovered about the makeup of matter and how scientists today continue to explore the nature of matter. Unit 2 consists of eight chapters organized around the theme of how energy affects matter. You will learn about how scientists developed the concept of energy, how energy affects matter, and how energy can be transformed from one form to another. Unit 3 covers the different branches of earth science: geology, the study of the solid part of the earth; meteorology, the study of the layer of gases that surrounds the earth; oceanography, the study of the oceans and the earth's surface beneath the ocean; and astronomy, the study of the universe. The fourth unit presents an introduction to biology, the study of living things. You will learn about living things and how they are classified, the structure and function of your own body, how living things pass on their traits to their offspring, and how living things interact with their environments. The chapter goals at the beginning of each chapter tell you what you will learn in that chapter. Each chapter is further iv