tailieunhanh - Lecture Biology (7th edition) - Chapter 4: Carbon and the molecular diversity of life

Chapter 4 - Carbon and the molecular diversity of life. All organisms are composed mostly of chemical structures based on the element carbon. This chapter builds upon information and concepts introduced in Chapters 2 and 3 and extends the descriptions and analysis to more detailed consideration of the carbon atom. | Lecture Biology (7th edition) - Chapter 4: Carbon and the molecular diversity of life Chapter 4 Carbon and the Molecular Diversity of Life PowerPoint Lectures for Biology, Seventh Edition Neil Campbell and Jane Reece Lectures by Chris Romero Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Overview: Carbon—The Backbone of Biological Molecules • All living organisms – Are made up of chemicals based mostly on the element carbon Figure Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Concept : Organic chemistry is the study of carbon compounds • Organic compounds – Range from simple molecules to colossal ones Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • The concept of vitalism – Is the idea that organic compounds arise only within living organisms – Was disproved when chemists synthesized the compounds in the laboratory In 1953, Stanley Miller simulated what were thought to be EXPERIMENT environmental conditions on the lifeless, primordial Earth. As shown in this recreation, Miller used electrical discharges (simulated lightning) to trigger reactions in a primitive “atmosphere” of H 2O, H2, NH3 (ammonia), and CH4 (methane)—some of the gases released by volcanoes. A variety of organic compounds that play key roles in living cells were RESULTS synthesized in Miller’s apparatus. Organic compounds may have been synthesized abiotically on the CONCLUSION early Earth, setting the stage for the origin of life. (We will explore Figure this hypothesis in more detail in Chapter 26.) Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Concept : Carbon atoms can form diverse molecules by bonding to four other atoms Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings The Formation of Bonds with Carbon • Carbon has four valence electrons • This allows it