细胞分子生物学化学基础.pptx

2.1 Atomic Bonds and Molecular Interactions第1页/共13页第2页/共13页2.2 Chemical Building Blocks of Cells第3页/共13页Amino Acids Differing Only in TheirSide Chains Compose ProteinsAlthough the chemical properties of such optical isomers are identical,their biological activities are distinct.Only L amino acids are found in proteins.第4页/共13页Five Different Nucleotides AreUsed to Build Nucleic Acids第5页/共13页Monosaccharides Joined by Glycosidic Bonds Form Linear and Branched Polysaccharides第6页/共13页Fatty Acids Are Precursors for Many Cellular Lipids第7页/共13页2.3 Chemical EquilibriumEquilibrium Constants Reflect the Extent of a Chemical ReactionChemical Reactions in Cells Are at Steady StateDissociation Constants for Binding Reactions Reflect the Affinity of Interacting Molecules第8页/共13页Buffers Maintain the pH of Intracellular and Extracellular Fluids第9页/共13页2.4 Biochemical EnergeticsSeveral Forms of Energy Are Important in Biological Systems Kinetic Energy(thermal energy,Radiant energy,Mechanical energy,Electric energy)Potential Energy(chemical potential energy,concentration gradient,Electric potential)Cells Can Transform One Type of Energy into Another第10页/共13页The Change in Free Energy Determines The Direction of a Chemical Reaction Hydrolysis of ATP Releases Substantial Free Energy and Drives Many Cellular Processes第11页/共13页第12页/共13页感谢您的观看！第13页/共13页