生物化学-绪论-课件.ppt

1、一、生物化学发展简历一、生物化学发展简历二、生物化学的基本内涵二、生物化学的基本内涵三、生物化学在专业学习中的地位与作用三、生物化学在专业学习中的地位与作用四、如何学好生物化学四、如何学好生物化学五、学习本课程的基本要求五、学习本课程的基本要求 是研究生命活动过程中是研究生命活动过程中物质基础物质基础 及其及其化学反应规律化学反应规律的一门科学。的一门科学。1)1)Functional groupsFunctional groups are clusters of atoms with characteristic structure and functions.2)2)Most biomol

2、eculesMost biomolecules contain more than one functional group.3)Different families of organic compounds result when hydrogen atoms on organic molecules are replaced by different functional groups.4)4)The distinct chemical propertiesThe distinct chemical properties of each functional group contribut

3、e to the behavior of any molecule that contains it.1)单糖、双糖单糖、双糖2)甘油、脂肪酸甘油、脂肪酸3)氨基酸氨基酸4)核苷酸核苷酸葡葡 萄萄 糖糖单单 糖糖双双 糖糖Fatty acidsStructure of an amino acid 1)多多 糖：淀粉、糖原、纤维素等糖：淀粉、糖原、纤维素等2)蛋白质：结构蛋白、酶、转录因子等蛋白质：结构蛋白、酶、转录因子等3)核核 酸：酸：DNA、RNA、dsRNA etcStarchGlycogen Cellulose Structure of cellulose as it occurs i

4、n a plant cell wall Lipids are composed of three fatty acids(usually)covalently bonded to a 3-carbon glycerol.v Functions:Long-term energy storage;Structural components;Hormones;insulators and cushions.Structure of a phospholipid,Phospholipids and glycolipids are important structural components of c

5、ell membranes.Phospholipids are modified so that a phosphate group(PO4-)is added to one of the fatty acids.The addition of this group makes a polar head and two nonpolar tails.Proteins are very important in biological systems as control and structural elements.The building block of any protein is th

6、e amino acids.HIV p17 protein and similarities of its structure to gamma interferon.Formation of a covalent bond between two Hydrogen atoims.Formation of covalent bonds in methaneTable Salt Crystal Formation of a crystal of sodium chloride.Each positively charged sodium ion is surrounded by six nega

7、tively charged chloride ions;likewise each negatively charged chloride ion is surrounded by six positively charged sodium ions.The overall effect is electrical neutrality.Ionic bondFormation of a hydrogen bond between the hydrogen side of one water molecule and the oxygen side of another water molec

8、ule.The presence of polar areas in the amino acids that makeup a protein allows for hydrogen bonds to form,giving the molecule a three-dimensional shape that is often vital to that proteins proper functioning.Electrostatic interactions Electrostatic interactions occur between oppositely charged atom

9、s or groups.An important aspect of all electrostatic interactions in aqueous solution is the hydration of ions.Because water molecules are polar,they are attracted to charged ions.As ions become hydrated,the attractive force between them is reduced,and the charged species dissolves in the water.Diss

10、olution of an ionically bonded compound,sodium chloride,by water molecules.van der Waals forces van der Waals forces are relatively week,transient electrostatic interactions.They occur between permanent and/or induced dipoles.They may be attractive or repulsive,depending on the the distance between

11、the atoms or groups involved.There are three types of van der Waals forces:Dipole dipole interactions Dipole induced dipole interactions Induced dipoles induced dipoles interactions.The mean van der Waals diameter of water is identical with that of isoelectronic neon(2.82).Hydrophobic interactionsAs

12、 soon as nonpolar substances are mixed with water,they coalesce into droplets because water-water interactions are stronger than water-nonpolar substance interactions.This process results from hydrophobic interactions.功能基团化学键构件分子生物大分子化学键化 学 键氢键（hydrogen bond）离子键（ionic）静电作用力（electrostatic interaction

13、）范氏作用力（van der Waals forces）疏水作用力（hydrophobic interactions）共价键（covalent bond）非共价键（non-covalent bond）生命活动过程是由数千化学反应生命活动过程是由数千化学反应组成的，相关联的化学反应形成组成的，相关联的化学反应形成代谢途径，不同的代谢途径连接代谢途径，不同的代谢途径连接形成代谢网络。形成代谢网络。Chemical reactionsMetabolic pathwaysMetabolic networksAB,BC,CD,CE,EFABCDCEFABCD EF 生物化学反应是由酶催化的，反应的生物化

14、学反应是由酶催化的，反应的基本原理是相同的。基本原理是相同的。氧化还原反应氧化还原反应亲核反应亲核反应异构化反应异构化反应水解反应水解反应合成反应合成反应etc 生物化学反应实现了生命必须的物质转生物化学反应实现了生命必须的物质转换、能量传递和信息交流的统一。换、能量传递和信息交流的统一。物质转换物质转换生化反应的表现形式生化反应的表现形式生命平台生命平台能量传递能量传递生化反应的催化动力生化反应的催化动力生命活力生命活力信息交流信息交流生化反应的目标实现生化反应的目标实现生命意义生命意义 生物化学反应发生在细胞中，生物化学反应发生在细胞中，体现出生命的系统性。体现出生命的系统性。生物分子的相互作用生物分子的相互作用细胞器之间的相互作用细胞器之间的相互作用细胞内的信号细胞内的信号细胞生命活动的协调与统一细胞生命活动的协调与统一etc l基础理论作用基础理论作用（学习后续课程的基础）（学习后续课程的基础）l实践动手作用实践动手作用（基本实验技能的培训）（基本实验技能的培训）l生物思想作用生物思想作用（生化的角度看生命现象）（生化的角度看生命现象）理 解掌 握了 解认 识概 括重 复记 忆阅 读方 法过 程