3.2 - ATP: Energy Currency of the Cell

• Why do cells need energy?

  Cells need energy to carry out important functions
• What functions to cells need energy for?

  • Mechanical work (beating cilia, muscle movement)
  • transport Work (pumping substances across membranes)
  • Chemical Work (providing energy to build complex molecules)
• What does ATP stand for?

  Adenosine Triphosphate
• What is ATP composed of?

  3 Phosphate Groups, Ribose Sugar, Adenine
• What is this diagram?

  ATP - Adenosine Triphosphate

  
• What reaction is going on?

  ATP Hydrolysis

  
• ATP + H2O —> ADP + Phosphate Group + Energy
• Energy Coupling - using energy released from one reaction to drive another reaction
• ATP can be used to attach a phosphate group to another molecule (phosphorylation) to supply it with ENERGY
• • The phosphate may make the molecule more reactive and more likely to undergo a spontaneous reaction
• ATP is used to kickstart the reaction!
• No ATP!

  Endergonic (∆G = +14.2 kJ/mol)

  —> Non-spontaneous
• ATP - The UniversL Energy Currency