A、He created the theory of germs and bacteria. B、He invented the vaccine against smallpox. C、He discovered a mechanism for the c

Today’s lecture will include the most outstanding achievements in biology as it relates to the medical sciences.
    Early in Greek history, Hippocrates began to study the human body and to apply scientific methods to the problems of diagnosis and the treatment of diseases. Un-like other physicians of his time, he discarded the theory that disease was caused by the gods.[8]Instead, he kept careful records of the symptoms and treatments, indicating the success or failure of the patient’s cure. He has been recognized as the father of modern medicine.
    About a century later, Aristotle began a scientific study of plants and animals, classifying more than 500 types on the basis of body structure. Because of his great contribution to the field,[9]Aristotle has been called the father of biology.
    By the first century A. D. , Dioscorides had collected a vast amount of information on plants, which he recorded in the now famous Materia Medica, a book that remained an authoritative reference among physicians for more than 1,500 years.
    During the Middle Ages, scientific method was scorned in favor of alchemy. Thus, medicine and biology had advanced very little from the time of the ancients until the 17 th century when[10]the English physician and anatomist William Harvey discovered a mechanism for the circulation of blood in the body.
7. What is this lecture mainly about?
8. What can we learn about Hippocrates from the lecture?
9. What can we learn about Aristotle from the lecture?
10. What was William Harvey’s contribution to medicine?