ATP

• What does ATP stand for?

  Adenosine Triphosphate
• ATP is a small, relatively simple nucleic acid molecule that serves as the main source of energy for cellular processes in living organisms, acting as a currency for energy transactions within cells.
• What is the role of ATP?

  Energy currency
• The body cannot directly get its energy from glucose, as it is not a direct energy source, instead, the body uses the energy released from breaking down glucose to drive phosphorylation of ADP. This makes ATP, which is an immediate energy source that cells can use up quickly.
• What is the product of phosphorylation of ADP?

  ATP
• The energy released from the breakdown of glucose is used to make ATP.
• The energy from ATP is required in anabolic reactions - building larger molecules from smaller molecules.
• What are anabolic reactions?

  Building reactions.
• The energy from ATP is required to move substances across the cell membrane through active transport or to move substances within the cell.
• The energy from ATP is required for muscle contraction in animals and in the conduction of nerve impulses, as well as many other cellular processes.
• ATP consists of three phosphate groups, one nitrogenous adenine base and one ribose sugar.
• How many carbons does a ribose sugar have?

  Five
• What is ATP made up of?

  Three phosphate groups, one nitrogenous adenine base and one ribose sugar.
• ATP is a nucleotide derivative because it is a modified form of a nucleotide.
• ATP is the most closely related to RNA as they both contain ribose sugars, whereas DNA contains a deoxyribose sugar.
• Energy released during the reactions of respiration is transferred to the molecule ATP, which provides a short-term store of chemical energy.
• Energy is stored in the phosphoanhydride bonds joining the phosphate groups, therefore meaning that there is a high amount of energy between the three phosphate groups. In order to release this energy, the bond must be broken, this happens through hydrolysis.
• Where is energy stored in ATP?

  In the phosphoanhydride bonds joining the phosphate groups
• How is energy released from the phosphate bonds in ATP?

  They are broken in a process called hydrolysis
• What is hydrolysis?

  Chemical reaction that breaks down a compound by adding water.
• What is the equation for the hydrolysis of ATP?

  ATP + H2O -> ADP + Pi + energy
• Describe the process of ATP hydrolysis?

  The phosphate bonds are broken by a hydrolysis reaction, which requires the use of water, this forms ADP, an inorganic phosphate group (Pi) and the release of energy, this hydrolysis is catalysed by the enzyme ATP hydrolase.
• What reaction breaks the phosphate bonds in ATP?

  Hydrolysis
• What molecule is required in a hydrolysis reaction?

  Water
• What is formed when ATP is hydrolysed?

  ADP (Adenosine Diphosphate), an inorganic phosphate group (Pi) and energy is released
• What does ADP stand for?

  Adenosine diphosphate
• What enzyme catalyses hydrolysis of ATP?

  ATP hydrolase
• The enzyme ATP hydrolyse can further catalyse ADP into AMP, and a second inorganic phosphate group, and thus release more energy.
• What does AMP stand for?

  Adenosine monophosphate
• What is Pi the symbol for?

  An inorganic phosphate group
• The hydrolysis of ATP can be coupled to other reactions within cells that need energy.
• What is energy coupling?

  Using energy released from one reaction to drive another reaction.
• What is an example of energy coupling?

  The sodium-potassium pump, where energy is released from the hydrolysis of ATP and is then used to power the pump that drives Na+ out of the cell and K+ into the cell.
• The inorganic phosphate group released in ATP hydrolysis can be used to phosphorylase other compounds, this often makes them more reactive.
• What is a use of inorganic phosphate groups released during ATP hydrolysis?

  Can be used to phosphorylase other compounds, this often makes them more reactive
• Organisms cannot build up large stores of ATP and it rarely passes through the cell membrane, this means that the cells must make ATP as and when they need it.
• Like most chemical reactions, the hydrolysis of ATP to ADP is reversible, this reverse reaction is known as ATP synthesis or phosphorylation.
• What is the reaction to form ATP called?

  Phosphorylation
• What type of reaction is phosphorylation?

  Condensation
• What is the equation for ATP phosphorylation?

  ADP + Pi + energy -> ATP + H2O