Bio Anki

• Why is water a good solvent

  It is polar
• What does polar mean


  When two atoms in a covalent bond have different electronegativities"
• Define Metabolite

  Any substance that is used or produced in a metabolic reaction
• what is Cohesion

  attraction between two of the same molecules
• What is adhesion

  Attraction between two different molecules
• What is a monomer

  A simple molecule from which polymers are made up of
• What is a polymer

  A chain of connected and repeating monomers.
• Define hydrolysis

  The breaking of a bond by the addition of a molecule of water
• What is a condensation reaction?

  The forming of bonds by removing a molecule of water
• What are the reducing sugars

  Fructose, glucose, galactose, maltose, lactose (FGG ML(S*))
• Why is sucrose different from the rest of FGG MLS?

  Sucrose is made up of two reducing sugars (glucose and fructose) but isn't a reducing sugar itself.
• What bond connects molecules of water?

  Hydrogen bonds
• Describe the bonds between water molecules

  A bond between a partially positive hydrogen atom of one molecule and the partially negative oxygen of another.
• Why is water polar?

  The oxygen atom is more electronegative than the hydrogen atoms as it is more massive.
• What is the general formula of reducing sugar?

  (CH2O)n"
• Structure of an Alpha glucose molecule


  "
• Structure of a Beta glucose molecule


  "
• What are the three polysaccharides needed for A level biology

  Starch, glycogen, cellulsoe
• Starch is made of a mixture of two similar polysaccharides, what are they.

  Amylose, Amylopectine
• Describe the structure of Amylose

  helical structure of alpha glucose
• Describe the structure of Amylopectin

  Branching chains of alpha glucose
• How is amylose suited for its role in organisms

  Its helical shape allows for effecient use of space making it a good storage molecule
• How is Amylopectin suited for its role in organisms

  Being branched creates many points for enzyme connection allowing for it to be quickly broken down into glucose
• Describe glycogen's structure

  Heavily branched chains of alpha glucose
• Describe Cellulose's structure

  Parallel chains of beta glucose connected by H-bonds
• Which of the polysaccharides are connected with 1-4 gylcocidic bonds?

  Amylose, amylopectin, cellulose
• Which of the polysaccharides are connected with 1-6 glycocidic bonds

  amylopectin, gylcogen.
• Where is starch found

  Starch storage organs in plants e.g potato tubers
• Where is gylcogen found

  liver and muscles of animals
• Where is cellulose found

  Cell walls of plants
• Use of starch

  Stores energy as glucose in plants
• Use of glycogen


  store of energy in animals
• Use of cellulose


  Provide structure and strength to the cell walls of plant cells.
• How do you test for reducing sugars

  The benedicts test- make a solution of the test materialAdd a roughly equal volume of benedict's solutionheat the solution in a water bath to 80oC for 5 minutes
• Positive result of the benedicts test


  A green, yellow, orange or brick red colour indicates a reducing sugar is present
• Non-reducing sugar test

  Acid hydrolysis:Make a solution of test materialadd a few drops of HCL to test solutionHeat in a water bath for a few minutesneutralise the acid with sodium hydrogen carbonatecarry out the benedicts test
• Testing for starch


  The material is shaken in water and iodine solution is added
• Positive result for the iodine test

  An inky blue-black colour indicates starch is present
• How do you carry out a quantative test for glucose?

  Carry out the benedicts test on a solution of unknown glucose concentrationcalibrate a colourimeter using a vial of distilled watertest a number of samples of solution of known glucose concentrationrecord the absorbsion/transmittionplot a graph for these resultstest the unknown sampleplot the result and compare to the line of best fit to find the concentration
• How do you test for lipids?

  Add lipid sample to ethanol in a clean and dry test tube. Shake to disolveAdd distilled water