xii Unit 7 The Body and How It Develops . . . 526 Chapter 16 Human Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . 528 Lesson 16.1 The Beginning of Life . . . . . . . . . . . . . . . . 530 Lesson 16.2 Child Development . . . . . . . . . . . . . . . . . 536 Lesson 16.3 Adolescence and Puberty . . . . . . . . . . . . 544 Lesson 16.4 Adulthood and Aging . . . . . . . . . . . . . . . 553 Chapter 16 Review and Assessment . . . . . . . . . . . . . 561 Chapter 17 The Body Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 564 Lesson 17.1 Supporting and Moving the Body . . . . 566 Lesson 17.2 Moving and Exchanging Substances . . . 574 Lesson 17.3 Digesting and Removing Substances . . . 581 Lesson 17.4 Controlling and Regulating the Body . . . 589 Chapter 17 Review and Assessment . . . . . . . . . . . . . 599 Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 602 Glossary/Glosario . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 604 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 633