biological molecules

• what is the formula for a sugar?

  c6h12o6
• name 3 monosaccharides ?

  fructose glucose galactose
• what are the 2 types of glucose?

  alpha and beta
• what reaction joins monosaccharides?

  condensation
• what bond is formed in carbohydrates?

  glycosidic bonds
• disaccharides ?


  maltose sucrose lactose
• what reaction breaks bonds?

  hydrolysis
• describe the test for sugars?

  benedicts , add benedicts regent and heat it if positive it turns brick red
• what is starch made up of?

  amylose and amylopectin
• structure of amylose?


  unbranched , alpha glucose , coiled compact
• structure of amylopectin ?

  branched , alpha glucose , side branches, released quickly
• features of starch?


  insoluble , doesn't affect water potential
• test for starch?


  add iodine , brown to blue black colour change
• what is cellulose made of?

  unbranched , beta glucose , hydrogen bonds
• structure of a triglyceride ?

  glycerol , 3 fatty acids
• what bond is in a triglyceride ?

  ester
• what makes a fatty acid unsaturated?

  a double bond within the carbon chain
• structure of a phospholipid?
• structure of a phospholipid?

  phosphate group , 2 fatty acids and glycerol
• the phosphate group is hydro....?


  hydrophilic
• the fatty acid tail is hydro....?


  hydrophobic
• lipids contain .... the amount of energy as carbohydrates?

  twice
• what do phospholipids make up in cells?

  bilayer of cell membrane
• the test for lipids?

  emulsion , shake with ethanol , pour into water , positive result is milky white
• what are proteins made up of?

  ammino acids
• general structure of ammino acids?

  carboxyl group , ammino group , R group and hydrogen
• bonds in polypeptides?


  peptide bonds
• levels of protein structure?


  primary , secondary ,tertiary , quaternary
• features of primary structure?


  sequence of ammino acids
• feature of secondary structure?

  hydrogen bonds , alpha helices and beta pleated sheets
• features of tertiary structure?

  more coiling and folding ,more hydrogen an ionic bonds ,disulphide bonds and 3d structure
• features of quaternary structure?

  multiple polypeptides joined by bonds
• test for proteins?


  biuret test , add NaOH then copper sulphate , positive result is purple
• what do enzymes do?

  catalyse metabolic reactions
• how do enzymes speed up reactions?

  lowering activation energy
• describe the lock and key model?

  substrate fits perfectly into active site , creates enzyme-substrate complex , enzyme unchanged after the reaction
• describe the induced fit model?

  enzyme binds to active site and changes the shape slightly , enzyme-substrate complex
• enzyme properties due to tertiary structure?

  active site shape determined by tertiary structure , if tertiary structure changed the enzyme won't function
• temperatures effect on enzymes?

  rise in temp = more vibration

  if temp rises too much bonds break

  enzyme denatures
• effects of PH on enzymes?

  most common level is 7

  pH above and below breaks hydrogen and ionic bonds

  enzymes denature