ATP

• What is ATP?

  Adenosine triphosphate
• Describe the structure of ATP

  • Ribose bound to a molecule of adenine and 3 phosphate groups
  • Nucleotide derivative
• Describe how ATP is broken down

  • ATP (+water) = ADP (adenine diphosphate) + Pi (inorganic phosphate)
  • Hydrolysis reaction, using a water molecule
  • Catalysed by ATP hydrolase (enzyme)
• Give 2 ways in which the hydrolysis of ATP is used in cells

  • Coupled to energy requiring reactions within cells e.g. active transport, protein synthesis
  • Inorganic phosphate released can be used to phosphorylate other compounds making them more reactive
• Suggest how the properties of ATP make it a suitable immediate source of energy for cells

  • Releases energy in small amounts/little energy lost as heat
  • Single reaction/one bond hydrolysed to release energy (so immediate release)
  • Can't pass out of cell
• Describe how ATP is resynthesised in cells

  • ADP + Pi = ATP (+water)
  • Condensation reaction, removing a water molecule
  • Catalysed by ATP synthase
  • During respiration and photosynthesis