1. Cells need energy to do all their work To generate and maintain its highly ordered structure (biosynthesis of macromolecules). To generate all kinds of movement. To generate concentration and electrical gradients

table 13-1 Some Signals to Which Cells Respond Antigens Cell surface glycoproteins/oligosaccharides Developmental signals Extracellular matrix components Growth factors Hormones Light Mechanical touch Neurotransmitters Odorants

It is beyond the scope of this class to understand the following. If only one equilibration is in effect, the pH of the solution is determined by one Henderson-Hasselbalch equation

1. Enzymes were among the first biological macromolecules to be studied chemically 1.1 Much of the early history of biochemistry is the history of enzyme research. 1.1.1 Biological catalysts were first recognized in studying animal food digestion and sugar fermentation with yeast (brewing and wine making)

Assay:化验,分析,测定。 Enzyme activity: unit() is defined as the amount of enzyme which convert 1 micromole (umol) of substrate to product(s) in 1 minute under specified conditions. Specific activity: enzyme activity expressed per unit mass of protein present. (units/mg)

1. Living matter is composed mostly of the lighter elements 1.1 The composition of living matter is strikingly different from that of its physical environment(1810s) 1.2 The elements found in living organisms also exist in nature(especially in seawater and atmosphere)

1. Biomembranes are organized, sheetlike assemblies consisting mainly of proteins and lipids 1.1 The functions carried out by membranes are diverse and indispensable for life. 1.1.1 Biomembranes give cells their individuality by separating them from the environment

8.1 Some Basics 273 quence in the cells DNA. A segment of a DNA molecule 8.2 Nucleic Acid Structure 275 that contains the information required for the synthesis 8.3 Nucleic Acid Chemistry 291 8.4 Other Functions of Nucleotides 300 the only known func- Watson

7.1 Monosaccharides and Disaccharides 239 att 7.2 Polysaccharides 247 mine the intracellular location or metabolic fate of these hybrid molecules, called glycoconjugates. This chap- 7.3 Glycoconjugates: Proteoglycans, Glycoproteins

The cellular respiration (complete oxidation of fuels) can be divided into three stages Stage I All the fuel molecules are oxidized to generate a common two-carbon unit, acetyl-CoA. Stage II The acetyl-CoA is completely oxidized