What Is an Animal? (pp. 410 416) This section explains the basic characteristics and major functions of animals. It also describes how biologists classify animals into groups and presents the different types of symmetry. Use Target Reading Skills Page 408 of your textbook has a sample showing how to take notes. As you read, take notes on the main ideas in the rest of the section and the important details that support each main idea. Think about the Key Concepts and Key Terms. Use the graphic organizer below to help you take notes. What Is an Animal? Questions Notes: Functions of Animals What are some major functions of animals? 193
What Is an Animal? (continued) Structure of Animals (p. 411) 1. What are anatomy and physiology? 2. List the three higher levels of organization in animals and the structure and function of each level. a. b. c. Functions of Animals (pp. 412 413) 3. What are four major functions of animals? a. b. c. d. 4. What is an adaptation? 194
Match the needs with how animals use them. Use in Animals Needs 5. Gives animals raw a. oxygen materials for growth and b. food energy 6. Needed by body cells to release the energy from food 7. Is the following sentence true or false? Most animals have a cavity inside their body where food is broken down into substances the body can use. 8. Why must animals maintain a stable environment within their bodies? 9. What are most animal movements related to? a. b. 10. Is the following sentence true or false? Some animals don t move from place to place. 11. What is sexual reproduction? 12. The joining of an egg cell and a sperm cell is called. 13. What is asexual reproduction? 14. Is the following sentence true or false? Asexual reproduction involves the joining of sex cells from two parents. 195
What Is an Animal? (continued) Symmetry (p. 414) 15. The balanced arrangement of an animal s body is called. 16. Because a butterfly can be divided into two halves that are mirror images, it has symmetry. 17. Animals with many lines of symmetry that all go through a central point have symmetry. 18. Is the following sentence true or false? Some animals have no symmetry. 19. Circle the letter of each sentence that is true about bilateral symmetry. a. Human bodies have bilateral symmetry. b. Animals with radial symmetry are usually larger and more complex than animals with bilateral symmetry. c. Bilateral symmetry allows for a streamlined, balanced body that moves quickly and efficiently. d. Most animals with bilateral symmetry have sense organs in their back ends. Classification of Animals (pp. 415 416) 20. Biologists classify animals in the animal kingdom into about 35 major groups, each of which is called a(n). 21. Look at the diagram of animal phyla in your textbook. Circle the letter of the animal group that is most closely related to birds. a. insects b. mammals c. amphibians d. reptiles 196
22. Is the following sentence true or false? Evidence suggests that all animals arose from single-celled ancestors. 23. What do biologists consider when they classify an animal? a. b. c. 24. Is the following sentence true or false? An animal that does not have a backbone is called a vertebrate. 197