inorganic ions RG

• What do inorganic ions have?

  an electric charge
• what is an ion?

  an atom (or group of atoms) that has an electric charge
• what is a cation?


  an ion with a positive charge
• what is an anion?


  an ion with a negative charge
• what is an inorganic ion?

  an ion which doesn't contain carbon

  (although there are a few exceptions
• what do inorganic ions not contain

  carbon
• Where are there inorganic ions?

  In solution, in the cytoplasms of cells and in the body fluids of organisms
• what does each ion have?

  a specific role, depending on its properties
• what does an ion's role determine?

  whether it is found in high or low concentrations
• what ions are an important part of haemoglobin?


  iron ions
• what ions are an important part of haemoglobin?


  iron ions
• what is haemoglobin

  a large protein that carries oxygen around the body, in the red blood cells
• what is haemoglobin made up of?

  4 different polypeptide chains. each with a iron ion in the centre
• why are the iron ions a key component of haemoglobin?

  it is the iron ions that binds to the oxygen in haemoglobin

  • when oxygen is bound, the Fe2+ (iron) ion temporarily becomes an Fe3+ ion, until oxygen is released
• what is determined by hydrogen (H+) ions

  pH
• how is pH calculated?

  based on the concentration of H+ ions in the environment

  • more H+ present = lower pH= more acidic the environment
• what are all affected by pH?


  Enzyme-controlled reactions
• what do sodium (Na+)ions do?

  help transport glucose and amino acids across membranes
• how can a molecule of glucose or an amino acid be transported into a cell (across the cell-surface membrane)?


  alongside Na+ ions

  • this is known as co-transport
• why are phosphate ions important?

  they are an essential component of ATP and DNA
• when is a phosphate ion known as a phosphate group?


  when it is attached to another molecule it is known as a phosphate group
• What contain phosphate groups?

  • DNA
  • RNA
  • ATP
• what store energy in ATP?

  the bonds between phosphate groups
• what do the phosphate groups in DNA and RNA allow nucleotides to do?

  allow nucleotides to join up to form the polynucleotides