Topic 13 Amino acids

• What is a swifter ion?

  Where an amino acid can have a permanent + and - charge but is neutral overall
• The same amino acid can act as a lowery bronstead base and acid
• What does a zwitter ion look like? [2]

  CH3

  |

  H3N^+-C-COO^-

  |

  H
• What is the optimum pH for zwitter ions? [1]

  7.3
• What are the two types of peptide links? [2]

  OH-H

  C=O-N-H
• What is the condensation product of a reaction? [1]

  H2O / water
• The number of peptide links= number of H2O molecules released
• Hydrolysis is the breaking of a bond in an acid or base conditions
• What is hydrolysis? [1]

  Hydrolysis is the breaking of a bond in cid or base conditions
• What condition is needed for a hydrolysis reaction? [2]

  Concentrated HCl (6.0 Moldm-3) is boiled under reflux for 24 hrs and is acid hydrolysis
• Look at notes for how hydrogen bonds are arranged in DNA/ proteins
• What are enzymes in terms of chemistry [7]

  enzymes act as a biological catalyst

  every enzyme has an area called its active site

  enzymes only work with specific substrates

  lock and key model

  active site and substrate are stereo specific

  only a substrate with a unique stereo specific orientation of bonds will be attracted into the enzyme

  some are inhibitors so they block the active site- how drugs work
• What is the structure of DNA? [4]

  DNA is made up of monomers called nucleotides: phosphate group, pentose sugar, and a base

  phosphate group: the phosphate group is an ion due to the negative charge on one of the oxygens

  Penrose sugar: a pentose sugar is made up of 5 carbons

  Base: adenine- thymine. Cytosine-guamine (listed on data sheet)
• To display hydrogen bonding between DNA bases, what is needed? [1]

  Base turns 90 degrees anticlockwise and is shown between the N and the H
• Where are the phosphodiester bonds created between DNA bases? [1]

  H off the sugar, OH off the phosphate
• What do you need to know about cisplatin? [4]

  It is a complex ion of platinum with 2 chloride ion ligands and two ammonia ligands in a square planar shape

  it is chloride on the same side

  transplatin is chloride on opposite sides

  cancer is controlled by cell division, for cells to divide DNA needs to replicate so needs to unwind. Cisplatin stops this so tumor cells stop reproducing
• What are the adverse effects of cisplatin in attempt to stop cancer? [4]

  Can effect healthy cells

  can cause hair loss

  supresses the immune system

  lessens side effects by giving small doses.
• Look at notes on how to draw cisplatin