carbohydrates

• Carbohydrates make up the greatest proportion of the body mass of organisms
• Carbohydrates

  Polyhydroxylated aldehydes and ketones commonly called sugars
• Types of carbohydrates

  • Simple sugars
  • Complex sugars
• Simple sugars (monosaccharides)

  Have the general formula CnH2nOn, where n varies from 3 to 8, and have a single aldose or ketose group
• Types of monosaccharides

  • Aldoses
  • Ketoses
• Aldoses

  Monosaccharides with an aldehyde group
• Ketoses

  Monosaccharides with a ketone group
• Isomers

  Molecules with the same molecular formulas but different structures
• Fischer projections

  A method of visualizing organic molecules in a line-structure format, named after Emil Fischer
• Classification of monosaccharides based on number of carbons

  • Triose
  • Tetrose
  • Pentose
  • Hexose
• Anomers


  Differences in geometry visible in the carbons of some sugar molecules
• Cyclic forms of monosaccharides


  Furanoses (5 carbons), pyranoses (6 carbons), septanoses (7 carbons), etc.
• Disaccharides


  Consist of two monosaccharides joined together by a glycosidic bond, formed through condensation reactions and broken down through hydrolysis
• Most carbohydrates found in our body are in their D-form
• Glycosidic bond

  Bond that joins monosaccharides together to form disaccharides and polysaccharides
• Condensation reaction


  Monosaccharides joined with loss of water to form disaccharides
• Hydrolysis


  Breaks disaccharides apart with addition of water to form monosaccharides
• Disaccharides


  • Lactose
  • Sucrose
• Lactose


  Disaccharide composed of galactose and glucose, found in human and cow's milk
• Sucrose


  Disaccharide composed of glucose and fructose, commonly known as table sugar
• Alpha glycosidic bond


  Oxygen of aldehyde/ketone group is beneath the ring structure
• Beta glycosidic bond


  Oxygen of aldehyde/ketone group is above the ring structure
• Polysaccharides


  Carbohydrates consisting of 10 to 1000 monosaccharide units
• Polysaccharides


  • Cellulose
  • Starch
• Cellulose


  Polysaccharide consisting of glucose units linked by beta-glycosidic bonds, provides structural support in plants
• Starch

  Polysaccharide consisting of glucose units linked by alpha-glycosidic bonds, serves as energy storage in plants
• Amylose

  Linear component of starch
• Amylopectin

  Branched component of starch
• Oligosaccharide

  Polysaccharide with less than 10 monosaccharide units
• Homopolysaccharide

  Polysaccharide containing only one type of monosaccharide
• Heteropolysaccharide

  Polysaccharide containing two or more types of monosaccharides
• Carbohydrates

  • Have a ketone or aldehyde group and many hydroxyl groups
• Monosaccharides

  Simple sugars that cannot be broken down into smaller groups
• Disaccharides

  Carbohydrates composed of two monosaccharides
• Polysaccharides

  Carbohydrates composed of 10 to thousands of monosaccharides
• Alpha anomeric form

  • OH group in carbon 1 and -CH2OH group in carbon 5 are pointed in opposite directions
• Beta anomeric form

  • OH group in carbon 1 and -CH2OH group in carbon 5 are pointed in the same direction
• Glycosidic bond

  Bond used to link sugar units in disaccharides and polysaccharides
• Sucrose

  Also known as table sugar
• Beta-glycosidic bond

  Bond that holds glucose units together in cellulose