Carbohydrates

• Carbohydrates


  Commonly known as sugars, quite polar and water-soluble, the most abundant biological molecules on Earth, have a variety of cellular functions including in energy storage and structure
• Monosaccharides


  The building blocks of carbohydrates, common monosaccharides include glucose and fructose, can react with other monosaccharides to form disaccharides, oligosaccharides, and polysaccharides
• Polysaccharides


  Glucose polymers that are important energy storage and structural molecules in both plants and animals, include cellulose and starch
• Cellulose


  • Water-insoluble and indigestible, the principal component of wood, provides the scaffolding that holds up most plants, giving rigidity to their cells
• Starch


  • An easily digestible compound made by plants to store energy for future use, widely enjoyed in potatoes, pasta, and bread
• Cellulose and starch


  Chemically differ only in how the glucose subunits are linked together, but this minor difference results in dramatically distinct properties
• Humans make a similar molecule for energy storage called glycogen
• Cellulose and starch illustrate the principle that structure affects function in biological systems