ATP

Question 1

3. What is the reaction catalysed by ATP synthase?

Answer 1

ADP + Pi ⟶ ATP + H2O a condensation reaction

Question 2

4. What is the reaction catalysed by ATP
   hydrolase?

Answer 2

ATP + H2O⟶ ADP + Pi a hydrolysis reaction

Question 3

5. Describe how ATP is resynthesised in in cells

Answer 3

5. Describe how ATP is resynthesised in in cells

Question 4

6. Give reasons why ATP is a suitable energy source for cells.

Answer 4

Releases relatively small amount of energy so little energy is lost as heat. It is a one-step reaction so it releases energy instantaneously. It can phosphorylate other compounds so it makes them more reactive. It can be rapidly re-synthesised, so it is readily available. It doesn’t leave cells, so it is readily available.

Question 5

7. How can the hydrolysis of ATP be used by cells.

Answer 5

To provide energy for other reactions; To add phosphate to other substances and make them more reactive or change their shape;

Question 6

8. Why is it important that ATP is continually synthesised?

Answer 6

ATP cannot be stored, it is an immediate source of energy; ATP only releases a small amount of energy at a time;

Question 7

9. Give examples of processes ATP are used in.

Answer 7

Metabolic process such as making starch from glucose, or polypeptides from amino acids. Muscle contraction. Active transport of molecules across plasma membranes. Secretion, as ATP is needed to form lysosomes. Activation of molecules, ATP can phosphorylate other compounds (such as enzymes) to make them more reactive.