Unit One Bacteria and Viruses 1
Unit Two The Living Cell 19
Unit Three Nuclear Transfer：A Brief History 33
Unit Four Cloning Hits the Big Time 47
Unit Five Senescence 61
Unit Six Gene Could Help Predict Colon and Lung Cancer Risk 72
Unit Seven Plant Cell Culture 80
Unit Eight New Generation of Vaccines 92
Unit Nine The Evolution of Sex Ratios 105
Unit Ten Interference and Ethics 116
Unit Eleven HIV and AIDS 138
Unit Twelve Stem Cell Basics 150
Appendix Ⅰ Model Tests 166
Appendix Ⅱ Common Affixes in English for Biology 180
Appendix Ⅲ Glossary 182
Appendix Ⅳ Periodicals＆Journals 196
Appendix Ⅴ Reference Websites 197
Appendix Ⅵ References 198
Appendix Ⅶ Answers to the Exercises 199