1.6 ATP

Question 1

What does ATP stand for?

Answer 1

Adenosine Triphosphate
(tri means it has 3 phosphates)

Question 2

What does ATP consist of?

Answer 2

ATP is a phosphorylated nucleotide made up of the nitrogenous base adenine, 5C ribose sugar and a chain of 3 phosphate groups

Question 3

Describe the condensation reaction for ATP

Answer 3

ADP + Pi form a phosphate bond between the phosphates in a condensation reaction catalysed by the enzyme ATP synthase to form ATP + H2O. It requires energy

Question 4

Describe the hydrolysis reaction for ATP

Answer 4

phosphate bonds are broken by the enzyme ATP hydrolase in a hydrolysis reaction to form ADP + Pi. Energy is released in small packets and is used by cell for active processes

Question 5

Are phosphate bonds stable or unstable?

Answer 5

Unstable - makes ATP a good energy source and a poor long term energy store
ATP is the immediate energy source as the cell cannot get energy directly from glucose

Question 6

What is ATP used for?

Answer 6

Energy requiring processes in cells such as:
• phosphorylation of compounds to make them more reactive eg glucose to glucose phosphate in glycolysis and photophosphorylation in plant cells during photosynthesis
OR
• Active transport - ATP provides the energy to change the shape of the carrier proteins in plasma membranes - moving molecules against a gradient
• Metabolic processes eg synthesising glycogen from glucose or polypeptides from amino acids
• Exocytosis - secretion/release of products from the cell
• Movement - muscle contraction, movement of cilia