3.1.6 ATP

Question 1

what does ATP stand for?

Answer 1

adenosine triphosphate

Question 2

describe the structure of ATP

Answer 2

• ribose bound to a molecule of adenine and 3 phosphate groups
• nucleotide derivative (modified nucleotide)

Question 3

describe how ATP is broken down

Answer 3

• ATP (+water) = ADP (adenosine diphosphate) + Pi (inorganic phosphate)
• hydrolysis reaction, using a water molecules
• catalysed by ATP hydrolase (enzyme)

Question 4

2 ways in which hydrolysis of ATP is used in cells

Answer 4

• coupled to energy requiring reactions within cells (releases energy) e.g. active transport, protein synthesis
• inorganic phosphate released can be used to phosphorylate (add phosphate to) other compounds, making them more reactive

Question 5

how is ATP resynthesised in cels

Answer 5

• ADP (adenosine diphosphate) + Pi (inorganic phosphate) = ATP (+water)
• condensation reaction, removing a water molecule
• catalysed by ATP synthase (enzyme)
• during respiration and photosynthesis

Question 6

how do the properties of ATP make it a suitable immediate source of energy for cells

Answer 6

• release energy in relatively small amounts/ little energy is lost as heat
• single reaction/one bond hydrolysed to release energy (so immediate release)
• cannot pass out of cell