(7) Cellular Respiration (E) Regulation of pathways through feedback inhibition (A) Role of ATP & Phosphorylation (B) The metabolic pathway of respiration: Glycolysis and the citric acid cycle (C) The metabolic pathway of respiration: electron transport chain & ATP synthesis (D) Substrates for Respiration

Cellular Respiration (a) State the role of ATP in the body Describe the structure of ATP and ADP + Pi Define the term ‘phopsphorylation’

Re-cap from last year! What does ATP stand for? How would you draw this molecule? What does it have to do with energy? What is ATP used for?

Role of Adenosine Triphosphate ATP is used to transfer energy to synthetic pathways and other cellular processes where energy is required (anabolic). ATP transfer energy from processes that make energy (catabolic) It acts as a link between the 2 types of reactions:

Role of Adenosine Triphosphate

Is there enough ATP in the body? Yes! The reason for this is because whenever the body needs it, ATP is produced and used up straightaway. If there is an increase in the demand of ATP (you go running and your muscles need energy) then there will automatically be an increase in the production of ATP. ATP is always made the same time it is used, therefore there is always a constant quantity of ATP in the body.

Uses of Adenosine Triphosphate ATP is present in all living cells and is required for any process that requires energy, for example: Muscular contraction Making new proteins Active transport Transmission of nerve cells

Structure of ATP and ADP + Pi 1 adenosine molecule + 3 inorganic phosphate molecules ADP + Pi (Adenosine Diphosphate) Energy is released when the bond breaks between the middle and terminal phosphate molecules, and therefore results in the formation of ADP and Pi (Inorganic phosphate) Adenosine Pi Pi Pi Energy-rich bond Adenosine Pi Pi Pi

Structure of ATP and ADP + Pi ADP + Pi can be converted back into ATP, which results in a reversible reaction: ATP ADP + Pi High energy state Low energy state The regeneration of ATP is an example of phosphorylation

Phosphorylation Phosphorylation is an enzyme controlled process by which a phosphate group is added to a molecule. As a result, the new molecule is more reactive. Another example would be the phosphorylation of glucose:

Phosphorylation of glucose ATP (high energy) ADP Glucose Glucose-6-phosphate (high energy)

Cellular Respiration (a) State the role of ATP in the body Describe the structure of ATP and ADP + Pi Define the term ‘phosphorylation’