carbohydrates

• Carbohydrates


  A large group of organic compounds occurring in foods and living tissues and including sugars, starch, and cellulose. They contain hydrogen and oxygen in the same ratio as water (2:1) and typically can be broken down to release energy in the animal body.
• Lipids


  A large and diverse group of naturally occurring organic compounds that are insoluble in water but soluble in nonpolar solvents. They include fats, oils, waxes, sterols, and triglycerides.
• Carbon atom


  • Can form up to four single bonds or a combination of single and double bonds with other carbon atoms or atoms of other non-metallic elements
  • Allows for the formation of diverse compounds upon which life is based
• Production of macromolecules


  Condensation reactions that link monomers to form a polymer
• Digestion of polymers


  Hydrolysis reactions that break down macromolecules into monomers
• Monosaccharides


  The simplest carbohydrates, which cannot be hydrolyzed into smaller carbohydrates
• Monosaccharides


  • Glucose, ribose, fructose, galactose
• Disaccharides


  Carbohydrates composed of two monosaccharides
• Disaccharides


  • Sucrose, maltose, lactose
• Polysaccharides


  Carbohydrates composed of many monosaccharides
• Polysaccharides


  • Starch, glycogen, cellulose, chitin
• Pentose sugars


  Monosaccharides that contain 5 carbon atoms
• Pentose sugars


  • Ribose, deoxyribose
• Hexose sugars


  Monosaccharides that contain 6 carbon atoms
• Hexose sugars


  • Glucose, fructose, galactose
• Glucose


  • Soluble in water
  • Easily transported in body fluids
  • Chemically stable
  • High energy yield from oxidation
• Starch


  A polysaccharide composed of amylose and amylopectin, used for energy storage in plants
• Glycogen


  A polysaccharide used for short-term energy storage in animals
• Starch and glycogen


  • Compact due to coiling and branching during polymerization
  • Relatively insoluble due to large molecular size
  • Easily built up or broken down by condensation and hydrolysis reactions
• Amylose


  A component of starch, consisting of long chains of alpha-glucose
• Amylopectin


  A component of starch, consisting of long chains of alpha-glucose with branching chains
• Cellulose


  A structural polysaccharide found in plant cell walls, composed of beta-glucose monomers in alternating orientation
• SI units are used to ensure scientists from different parts of the world have the same standard system of measurements
• SI unit prefixes


  kilo- (k) x 10^3, centi- (c) x 10^-2, milli- (m) x 10^-3, micro- (μ) x 10^-6, nano- (n) x 10^-9
• 250 mm expressed in μm is 250,000 μm
• Amylose


  Amylopectin consists of long chains of alpha glucose with (glycosidic) bonds between carbon-1 and carbon-4
• Amylopectin


  At every 20th glucose molecule an additional glucose molecule bonds at C-6, resulting in a branched structure
• Amylopectin


  Glucose molecules can be added by condensation reactions or removed by hydrolysis reactions
• Glycogen


  Polysaccharide used for short term energy storage in animals
• Glycogen molecule


  • Composed of chains of alpha glucose with bonds between carbon-1 and carbon-4
  • Many branches of alpha glucose chains are present with alpha glucose bonding to carbon-6
  • Glycogen is an insoluble compact molecule, due to its many branches and coiling during polymerization
• Cellulose


  • Alternating orientation of beta-glucose monomers, giving straight chains that can be grouped in bundles and cross-linked with hydrogen bonds
• Cellulose


  Unbranched polysaccharide composed of beta glucose molecules which is found in the cell wall of plants
• Cellulose Structure


  1. Cellulose molecules consists of long chains of beta glucose molecules bonded between carbon-1 and carbon-4

  2. Every second beta glucose molecule is flipped, resulting in straight chains of cellulose molecules
• Cellulose Microfibrils


  Cellulose molecules form groups, known as microfibrils, held together by hydrogen bonds
• Cellulose Microfibrils


  • Have high tensile strength, allowing them to maintain the structural integrity of the cell walls of plants
• Glycoproteins


  • ABO antigens
• Glycoproteins


  • Integral proteins located within phospholipid bilayers of cells
  • Always have a chain of carbohydrates attached
  • The carbohydrate on the glycoprotein has a specific shape and can act as an antigen
• Roles of Glycoproteins


  • Cell to Cell Adhesion
  • Receptors
  • Cell to Cell Communication
  • Immune Response
• ABO Blood Groups


  • Glycoproteins act as antigens, if the glycoprotein is not recognized as self by the immune system
  • Antigens are substances which stimulate an immune response and the production of antibodies
• ABO Blood Groups


  • Red blood cells (erythrocytes) can have antigen A or antigen B
  • Blood Type A has antigen A and antibodies B
  • Blood Type B has antigen B and antibodies A
  • Blood Type AB has antigens A and B and no antibodies
  • Blood Type O has no antigens and antibodies A and B