Carbohydrates

• Biomolecules


  Any of the substances that are produced by cells and living organisms
• Major types of biomolecules

  • Carbohydrates
  • Lipids
  • Nucleic acids
  • Proteins
• Carbohydrates


  The body's most important and readily available source of energy, necessary part of a healthy diet
• Carbohydrates are the most abundant and widespread organic substances in nature and are essential constituents of all living things
• Macronutrients


  One of the three main ways the body obtains energy or calories
• Sources of carbohydrates


  • Sugars and fibers found in fruits and vegetables
  • Grains
  • Milk products
• Classifications of carbohydrates


  • Monosaccharides
  • Disaccharides
  • Polysaccharides
• Monosaccharides


  Simple sugars, number of carbons usually ranges from 3 to 7
• Monosaccharides


  • Glucose
  • Galactose
  • Fructose
• Disaccharides


  Formed when two monosaccharides undergo a dehydration reaction
• Disaccharides


  • Lactose
  • Maltose
  • Sucrose
• Polysaccharides


  Long chain of monosaccharides linked by glycosidic bonds
• Polysaccharides


  • Starch
  • Glycogen
  • Cellulose
• Reducing sugars


  Sugars that can be oxidized by mild oxidizing agents, have free aldehyde or ketone functional group
• Non-reducing sugars


  Sugars that are not oxidized by mild oxidizing agents
• Benedict's solution test


  1. Blue - no reducing sugars

  2. Green/yellow-green - traces of reducing sugars

  3. Orange/red-orange - moderate traces of reducing sugars

  4. Brick red - large amount of reducing sugars
• Fehling's solution test


  1. Blue - no reducing sugars

  2. Reddish-brown precipitate - presence of reducing sugars
• Iodine test


  1. Yellowish - no starch

  2. Black/dark color - presence of starch
• Arthropods like insects and crustaceans have an exoskeleton made of the polysaccharide chitin