ATP

Question 1

What is the importance of ATP?

Answer 1

Plants and animal cells require energy for processes such as active transport, DNA replication, cell division and protein synthesis.
Plant and animal cells release energy from glucose in the process of respiration.
However a cell cannot get its energy directly from glucose so in respiration the energy released from glucose is used to make ATP.

Question 2

What is ATP?

Answer 2

adenosine triphosphate

Question 3

What is the structure of ATP?

Answer 3

a single molecule of ATP is a nucleotide derivative (a modified form of a nucleotide) and is formed from a molecule of ribose, a molecule of adenine and three phosphate groups.

Question 4

What happens once ATP is made?

Answer 4

it diffuses to the part of the cell that needs energy and the energy is stored in high energy bonds between the phosphate groups which is released by hydrolysis reactions.

Question 5

What happens when energy is needed by a cell?

Answer 5

ATP is hydrolysed into ADP (adenosine diphosphate) and Pi (inorganic phosphate) - hydrolysis reaction that can be catalysed by the enzyme ATP hydrolase

ATP + H2O → ADP + Pi

Question 6

What prevents the energy being lost by heat in ATP hydrolysis?

Answer 6

ATP hydrolysis can be ‘coupled’ to other energy - requiring reactions in the cell which means the energy released can be used directly to make the coupled reaction happen rather than being lost as heat

Question 7

What is phosphorylation?

Answer 7

the released inorganic phosphate can be used by being added to another compound to make it more reactive

Question 8

How can ATP be resynthesised?

Answer 8

in a condensation reaction between ADP and Pi which can be catalysed by the enzyme ATP synthase during photosynthesis or respiration