ACCTG 1 Lecture Notes - Lecture 10: Simple Cell, Deductive Reasoning, Scriptio Continua
Document Summary
It is generally accepted that the earth is around 4. 6 billion years old. Geology study of surface of earth. It tries to understand its past by analyzing the many layers of sediments that have been formed. Cambrian explosion sudden presence of fossils in geological records, starting some 542 million years ago. Often presented as the beginning of real" life because animals that suddenly appeared, resembled those in current life. There were two important developments in those 4 billion years . Emergence of organic life forms simple cells complex cells multicellular life. Start of photosynthesis production of oxygen first by bacteria from water and then by plants from carbon dioxide. The 540 million years since the cambrian explosion are divided into three eras: Paleozoic era (540-250 million) in the beginning, animals of cambrian explosion thrived and were accompanied by other life forms. This period saw emergence of fish, land plants, insects, amphibians and reptiles.
