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 and polymers

  • Glucose (monomer)
  • Amino acids (monomers)
  • Nucleotides (monomers)
  • Starch (polymer)
  • Cellulose (polymer)
  • Glycogen (polymer)
  • Proteins (polymer)
  • DNA/RNA (polymer)
• 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
• Monosaccharide


  One sugar unit
• Disaccharide


  Two sugar units joined together
• Polysaccharide


  Many sugar units joined together
• 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, provides chemical energy
• Cellulose


  • Structural strength in plant cell walls
• Glycogen

  • Stored in animals, mainly in liver and muscle cells
• Starch and glycogen are made from alpha glucose, cellulose is made from beta glucose
• Starch has 1-4 and 1-6 glycosidic bonds, cellulose has only 1-4 bonds, glycogen has both 1-4 and 1-6 bonds
• Amylose


  Unbranched starch polymer
• Amylopectin


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


  • Long straight chains that line up in parallel and are held together by hydrogen bonds, providing structural strength
• Glycogen

  • More branched than starch, can be more readily hydrolyzed back into glucose
• Triglycerides


  Lipid with 3 fatty acid chains attached to a glycerol molecule
• Phospholipids

  Lipid with 2 fatty acid chains and a phosphate group attached to a glycerol molecule
• Triglyceride formation


  3 condensation reactions, 3 ester bonds formed, 3 water molecules removed
• Saturated fatty acids


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


  • At least one double bond between carbon atoms
• Triglycerides


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


  • Hydrophilic head, hydrophobic tails, can form bilayer in water
• Amino acid


  Monomer that makes up proteins, has central carbon, hydrogen, amine group, carboxyl group, and variable R group
• Dipeptide formation


  Condensation reaction, peptide bond formed, water removed
• Polypeptide formation


  Multiple amino acids joined by peptide bonds
• Primary structure

  Order or sequence of amino acids in a polypeptide chain
• Secondary structure

  Folding or twisting of the polypeptide chain, held by hydrogen bonds
• Tertiary structure


  Further folding of the polypeptide chain, held by ionic, hydrogen, and disulfide bonds
• Quaternary structure


  Protein made up of more than one polypeptide chain
• Enzymes


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


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