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Chapter 3: Biological Molecules At a Glance

Case Study: Improving on Nature?

3.1 Why Is Carbon So Important in Biological Molecules?

3.2 How Are Organic Molecules Synthesized?

• Biological Molecules Are Joined Together or Broken Apart by Removing or Adding Water

3.3 What Are Carbohydrates?

• There Are Several Monosaccharides with Slightly Different Structures
• Disaccharides Consist of Two Single Sugars Linked by Dehydration Synthesis
• Polysaccharides Are Chains of Single Sugars

3.4 What Are Lipids?

• Oils, Fats, and Waxes Are Lipids Containing Only Carbon, Hydrogen, and Oxygen

Health Watch: Cholesterol—Friend and Foe

• Phospholipids Have Water-Soluble "Heads" and Water-Insoluble "Tails"
• Steroids Consist of Four Carbon Rings Fused Together

3.5 What Are Proteins?

• Proteins Are Formed from Chains of Amino Acids
• Amino Acids Are Joined to Form Chains by Dehydration Synthesis
• A Protein Can Have Up to Four Levels of Structure
• The Functions of Proteins Are Linked to Their Three-Dimensional Structures

3.6 What Are Nucleic Acids?

• DNA and RNA, the Molecules of Heredity, Are Nucleic Acids
• Other Nucleotides Act as Intracellular Messengers, Energy Carriers, or Coenzymes

Case Study Revisited: Improving on Nature?

Links to Life: A Hairy Subject