biomolecules

• Biomolecules will be the topic for weeks 3 and 4 of grade 10 science
• Biomolecule


  Any molecule that is produced by a living organism and includes large macromolecules such as proteins, polysaccharides, lipids and nucleic acids
• Biomolecules are obtained from food
• Main types of biomolecules

  • Carbohydrates
  • Proteins
  • Nucleic acids
  • Lipids
• Carbohydrates


  The primary energy source of our body, which are sugars
• Monomer


  The building block or smaller unit from which larger molecules are made
• Monosaccharides (simple sugars)


  • Glucose
  • Fructose
  • Galactose
• Disaccharides


  Double sugars formed by combining two monosaccharides
• Disaccharides


  • Maltose
  • Lactose
  • Sucrose
• Polysaccharides


  Complex sugars made up of many monosaccharides
• Polysaccharides


  • Starch
  • Glycogen
  • Cellulose
  • Chitin
• Iodine test for starch

  1. Add iodine to food/material

  2. Violet colour indicates presence of starch
• Benedict's test for simple carbohydrates

  1. Add Benedict's solution to food

  2. Colour change from blue to green, yellow, orange, red indicates presence and amount of simple carbohydrates
• Proteins


  Body building molecules that help us grow, transport molecules, and control chemical reactions
• Monomer for proteins


  Amino acid
• Proteins


  • Soy albumin
  • Egg white
  • Hemoglobin
  • Enzymes
• Biuret test for proteins

  1. Add biuret reagent to food

  2. Colour change from blue to purple indicates presence of proteins
• Nucleic acids


  Important components in heredity, present in DNA
• Lipids


  Energy storing molecules, provide protection and waterproof covering
• Monomer for lipids


  Fatty acids
• Types of lipids


  • Steroids
  • Cholesterol
  • Fats
  • Oils
  • Waxes
• Saturated fats


  Solid at room temperature
• Unsaturated fats


  Liquid at room temperature
• Ethanol emulsion test for lipids

  1. Add ethanol to food

  2. Presence of lipids indicated by cloudy emulsion