Chapter 5 - The structure and function of large biological molecules. In this chapter, you should be able to: List and describe the four major classes of organic molecules; Explain: monomers, polymers, dehydration synthesis with the type of covalent bond for each; distinguish between monosaccharides, disaccharides, and polysaccharides;. | Chapter 5 The Structure and Function of Large Biological Molecules Overview: The Molecules of Life All living things are made up of four classes of large biological molecules: carbohydrates, lipids, proteins, and nucleic acids. Within cells, small organic molecules are joined together to form larger molecules. Macromolecules are large molecules composed of thousands of covalently connected atoms. Molecular structure and function are inseparable. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Why do scientists study the structures of macromolecules? Figure Macromolecules are polymers, built from monomers A polymer is a long chain-like molecule consisting of many similar building blocks. These small building-block molecules are called monomers. Three of the four classes of life’s organic molecules are polymers: Carbohydrates Proteins Nucleic acids Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings A condensation reaction or more specifically a dehydration reaction occurs when two monomers bond together through the loss of a water molecule: dehydration synthesis = build by removing HOH. Enzymes are organic catalysts = macromolecules that speed up chemical reactions. Polymers are disassembled to monomers by hydrolysis: breaking down by adding HOH. The Synthesis and Breakdown of Polymers Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The synthesis and breakdown of polymers Short polymer HO 1 2 3 H HO H Unlinked monomer Dehydration removes a water molecule, forming a new bond HO H2O H 1 2 3 4 Longer polymer (a) Dehydration reaction in the synthesis of a polymer HO 1 2 3 4 H H2O Hydrolysis adds a water molecule, breaking a bond HO H H HO 1 2 3 (b) Hydrolysis of a polymer Figure The Diversity of Polymers Each cell has thousands of different kinds of macromolecules. Macromolecules vary among cells of an organism, vary more within a species, . | Chapter 5 The Structure and Function of Large Biological Molecules Overview: The Molecules of Life All living things are made up of four classes of large biological molecules: carbohydrates, lipids, proteins, and nucleic acids. Within cells, small organic molecules are joined together to form larger molecules. Macromolecules are large molecules composed of thousands of covalently connected atoms. Molecular structure and function are inseparable. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Why do scientists study the structures of macromolecules? Figure Macromolecules are polymers, built from monomers A polymer is a long chain-like molecule consisting of many similar building blocks. These small building-block molecules are called monomers. Three of the four classes of life’s organic molecules are polymers: Carbohydrates Proteins Nucleic acids Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings A .
