Introductory text for freshman to junior level students in human or animal physiology. The unique integrated approach helps students see the big picture. Silverthorn's problem-centered focus develops students' critical thinking and problem-solving skills by helping them connect facts and concepts and apply them to real-world situations. An emphasis on the changing nature of scientific knowledge includes chapter by chapter integration of the latest research in cellular and molecular biology. Each chapter presents physiology as a dynamic field with numerous unanswered questions that merit further investigation.