he contents of the book have been updated. All of the chapters have been expanded and partially rewritten, particularly the following:

- Biology of the Cell (updated and expanded)
- Genetics and Evolution (new)
- Musculoskeletal System (17 new illustrations)
- Heart and Vascular System (new, clearer organization)
- Blood, Immune System and Lymphatic Organs (detailed coverage of the immune system, in line with the latest discoveries)
- Endocrine Organs (updated with many new illustrations)
- Digestive System (completely revised, including new sections on Antioxidants and Medicinal Herbs
- Reproduction, Development and Birth (with new, detailed coverage of the fertilization process)
- Central and Peripheral Nervous System (blood supply to the brain has been added)