Overview of Biological Macromolecules

May 20, 2025

Biological Macromolecules (Bio 111, Chapter 3)

3.1 Macromolecule Synthesis

Objectives:

  • Understand macromolecule synthesis
  • Explain dehydration and hydrolysis reactions

Key Terms:

  • Carbohydrates, Lipids, Proteins, Nucleic Acids: Four major classes of biological macromolecules.
  • Organic Molecules: Contain carbon, essential for life, can form stable bonds.
  • Monomers and Polymers: Monomers are building blocks that combine to form polymers.

Reactions:

  • Dehydration Synthesis: Combines monomers into polymers by removing water (Hâ‚‚O).
  • Hydrolysis: Breaks down polymers into monomers by adding water.

Enzymes:

  • Enzymes are proteins that speed up chemical reactions.
  • Specific to certain reactions; e.g., sucrose enzyme only works on sucrose.

3.2 Carbohydrates

Objectives:

  • Understand the role of carbohydrates in cells
  • Explain carbohydrate classifications

Types:

  • Monosaccharides: Simple sugars like glucose, fructose, galactose.
  • Disaccharides: Two monosaccharides linked together; e.g., sucrose (glucose + fructose).
  • Polysaccharides: Long chains of monosaccharides, e.g., glycogen, starch, cellulose.

Function:

  • Provide energy, primarily as glucose.
  • Polysaccharides serve as storage forms (e.g., glycogen in animals).

3.3 Lipids

Objectives:

  • Describe four major types of lipids
  • Explain roles of fats
  • Differentiate between saturated and unsaturated fatty acids

Types of Lipids:

  • Fats and Oils: Long-term energy storage; saturated fats are solid at room temp, unsaturated fats are liquid.
  • Waxes: Provide waterproofing on plants and animals.
  • Phospholipids: Make up cell membranes, have hydrophilic heads and hydrophobic tails.
  • Steroids: Includes cholesterol, important for hormones.

Characteristics:

  • Nonpolar hydrocarbons, hydrophobic.

3.4 Proteins

Objectives:

  • Describe functions of proteins
  • Understand relationship between amino acids and proteins

Structure:

  • Made up of amino acids (monomers) linked by peptide bonds.
  • Four levels of organization: Primary, Secondary, Tertiary, Quaternary.
  • Structure is critical to function.

Functions:

  • Wide range of functions: enzymes, structural components, transport, defense, etc.

3.5 Nucleic Acids

Objectives:

  • Describe nucleic acid structure
  • Know the difference between DNA and RNA

Components:

  • Nucleotides: Monomers of nucleic acids, composed of a nitrogenous base, a sugar, and a phosphate group.

Types:

  • DNA (Deoxyribonucleic Acid): Double-stranded, stores genetic information.
  • RNA (Ribonucleic Acid): Single-stranded, involved in protein synthesis.

Role:

  • DNA stays in the nucleus, RNA travels for protein synthesis.

Study Tips:

  • Review key differences between dehydration synthesis and hydrolysis.
  • Familiarize yourself with different types of carbohydrates, lipids, and proteins.
  • Understand the structural differences and functions of DNA and RNA.
  • Use interactive elements and videos provided for deeper understanding.