inorganic ions

• Inorganic ions

  • Phosphate
  • Hydrogen
  • Iron
  • Sodium
• Inorganic ions

  • Occur in solution in the cytoplasm and body fluids of organisms
  • Some in high concentrations and others in very low concentrations
  • Each type of ion has a specific role, depending on its properties and these roles are relevant in a range of topics across the A Level
• Phosphate


  Attached to other molecules as a phosphate group, for example: in DNA nucleotides, enabling nucleotides to join together forming phosphodiester bonds; in ATP-bonds between these store / release energy
• Hydrogen

  • Maintain pH levels in the body
  • Too much H = acidic (low pH)
  • Too little H alkaline (high pH)
  • Affects rate of enzyme-controlled reactions as can cause enzymes to denature
• Iron

  • Component of (haem group of) haemoglobin which is contained in red blood cells
  • Transports oxygen around the body - oxygen temporarily binds to it, so it becomes Fe3+
• Sodium


  • Co transport of glucose and amino acids across cell membranes
  • Involved in generating nerve impulses and muscle contraction (year 2)