biological molecules

• Monomers are smaller units which can create larger molecules and the polymers are made from lots of monomers which are bonded together
• Examples of monomers


  • Glucose
  • Amino acids
  • Nucleotides
• Examples of polymers


  • Starch
  • Cellulose
  • Glycogen
  • Proteins
  • DNA
  • RNA
• Condensation reaction to create polymers


  1. Joining two molecules together

  2. Creating a chemical bond

  3. Removing water
• Hydrolysis reaction to break apart polymers

  1. Breaking a chemical bond between two molecules

  2. Involves the use of water
• Monosaccharides


  • Glucose
  • Fructose
  • Galactose
• Disaccharides


  • Sucrose
  • Maltose
  • Lactose
• Polysaccharides


  • Starch
  • Cellulose
  • Glycogen
• Alpha glucose


  Hydrogen atom on top, hydroxyl group on bottom of carbon 1
• Beta glucose


  Hydroxyl group on top, hydrogen atom on bottom of carbon 1
• Glycosidic bond


  Chemical bond that forms between two monosaccharides to create a disaccharide
• Maltose is made from glucose + glucose, lactose is made from glucose + galactose, sucrose is made from glucose + fructose
• Starch


  • Stored in plants as a source of glucose
  • Made from alpha glucose
• Cellulose


  • Structural component in plant cell walls
  • Made from beta glucose
• Glycogen


  • Stored in animals as a source of glucose
  • Made from alpha glucose
• Starch and glycogen have 1-4 and 1-6 glycosidic bonds, cellulose has only 1-4 glycosidic bonds</b>
• Amylose


  Unbranched polymer of starch
• Amylopectin


  Branched polymer of starch
• Polysaccharides are large and insoluble, so they don't affect water potential or osmosis
• Cellulose


  • Long straight chains held together by hydrogen bonds, providing structural strength
• Glycogen


  • Highly branched, can be readily hydrolyzed to release glucose
• Lipids


  • Triglycerides
  • Phospholipids
• Condensation reaction to form triglycerides

  3 fatty acids join to glycerol, 3 water molecules removed
• Ester bond


  Bond that forms between fatty acids and glycerol in triglycerides
• Saturated fatty acid


  No double bonds between carbon atoms, fully saturated with hydrogen
• Unsaturated fatty acid


  At least one double bond between carbon atoms
• Triglycerides


  • High ratio of energy-storing C-H bonds, can act as metabolic water source, do not affect water potential
• Phospholipids


  • Hydrophilic head, hydrophobic tails, form bilayer in water
• Amino acids


  • Central carbon, hydrogen, variable R group, amino group, carboxyl group
• Condensation reaction to form dipeptide


  Water removed, peptide bond forms
• Condensation reactions to form polypeptide


  Multiple amino acids joined by peptide bonds
• Primary structure


  Sequence of amino acids in polypeptide chain
• Secondary structure


  Folding of polypeptide chain into alpha helix or beta pleated sheet, held by hydrogen bonds
• Tertiary structure


  Further folding of polypeptide into unique 3D shape, held by ionic, hydrogen and disulfide bonds
• Quaternary structure


  Multiple polypeptide chains assembled into final protein structure
• Enzymes


  • Proteins in tertiary structure that catalyze reactions by lowering activation energy
  • Each enzyme is specific to one reaction due to unique active site shape
• Induced fit model


  Enzyme active site slightly changes shape to mold around substrate, putting strain on bonds to lower activation energy
• Active site


  Complementary in shape to a particular substrate
• Lock and key model

  Enzyme's active site is complementary in shape to the substrate
• Induced fit model


  Enzyme's active site slightly changes shape to mould around the substrate