knowledge-1 BM

• Carbohydrates function- carbohydrates are respiratory substrate in cells as well as structural components in plasma membranes and cells wall.
• Lipids function- lipids form the bilayer in plasma membranes , some are hormones and some are respiratory substrate.
• proteins function- form components of many cellular structures , enzymes ,chemical messengers and blood components.
• nucleic acids-form the genetic code for protein production.
• monomers are single smaller sub-units that make up larger molecules.
• polymers are large molecules made up of a large number of monomers.
• monomers are joined by condensation reactions , with the elimination of water.
• polymers are split via hydrolysis , using a water molecule.
• Carbohydrates:

  • are made of monosaccharides for example glucose
  • multiple monosaccharides joined by condensation are called polysaccharides such as glycogen.
  • Between two monosaccharides a glycosidic bond is formed via condensation
  • to test for sugars you use a benedicts solution whereas for starch iodine is used.
• Lipids:

  • the monomers of lipids are glycerol and fatty acids
  • some examples of polymers that are lipids are triglycerides ( are made up of one glycerol and three fatty acids) and phospholipids (made up of two fatty acids and one phosphate)
  • contain ester bonds
  • to test for lipids you use the emulsion test with ethanol.
• Disaccharides are made of two monosaccharides joined by a glycosidic bond examples are as follows

  • glucose + glucose = maltose
  • glucose + fructose =sucrose
  • glucose + galactose = lactose .
• Triglycerides are insoluble in water as they are non-polar
• phospholipids have a hydrophilic head and hydrophobic tails and form plasma membranes.
• isomers are molecules with the same molecular formula but different structural formulae.
• Glucose has two isomers: alpha glucose and beta glucose
• glycogen and starch are polysaccharides made of alpha glucose
• cellulose is a polymer made of beta glucose molecules joined together by glycosidic bonds.
• saturated fatty acids contain no double bonds between carbon atoms
• unsaturated fatty acids contain double bonds between carbon atoms
• Distillation series:

  • V1 x C1 = V2 x C2
  • where V1= volume of stock solution needed , C1 is concentration of the stock solution , V2 is volume of dilution and C2 is concentration of dilution.
• proteins contain peptide bonds
• triglycerides are not usually classified as a polymer due to the fact that the monomer do not form a chain.
• the combination of 1,3 and 1,4 glycosidic bonds form a coiled structure
• to test for a reducing sugar:

  • add hydrochloric acid
  • boil
  • conducts benedicts test
• ethanol test:

  • add sample to ethanol
  • add water
  • shake
  • if white emulsion forms then test is positive
• glycogen:

  • helical shape
  • branched
  • contains 1,4 and 1,6 bonds
• amylopectin:

  • 1,4 and 1,6 bonds
  • not helical
  • branched