生物化学Chapter1下.pptVIP

2002年 科学出版社 356 pages 701 pages, with over 7000 references cited! The Foundations of Biochemistry (Chapters 1-2) To be lectured by Professor Zengyi Chang (昌增益 教授） March 3, 2006 Living organisms are classified into various types Inhabit extreme environments Common progenitor Organisms can be classified into three domains based on genetic relationships Organisms can also be classified based on their biochemical differences (energy and carbon sources) Energy sources Carbon sources Major features of living organisms Living organisms differ from inanimate objects in certain aspects Being chemically complex and highly organized. Extract, transform and use energy (matter) from their environment (metabolism, being never at equilibrium with their environment ). Be capable of precise self-reproduction and self-assembly (heredity and self-perpetuation). Being able to sense and respond to alterations in their surroundings. Being formed by evolution. Life depends on creating duplicating order in a chaotic environment. Cell is the structural and functional unit of living organisms made up of thousands of different types of molecules in highly organized self-assembled structures. The whole is greater than the sum of the parts! Fig. 3-26 Universal features of a living cell. Cellular Foundations: Structure of prokaryotic and eukaryotic Cells Cells are the basic structural and functional life units where biomolecules are produced (and degraded) and function, with thousands of biochemical reactions occur in regulated ways. Biomolecules and biochemical reactions are meaningful only when viewed in the context of biological structure! Prokaryotic (“before nucleus”) cells lack an internal membrane system (i.e., having no organelles). Escherichia coli (E. coli) is the best-studied prokaryote. Cytoplasm Contains many metabolic enzymes and metabolites. An E. coli cell in dividing The cytoplasm (shown being E. coli) is crowded with all types of biomolecules or biomole