PMT ATP Questions

Question 1

Water is used to hydrolyse ATP.
Name the two products of ATP hydrolysis.

Answer 1

Adenosine diphosphate and (inorganic) phosphate;

Question 1

Describe how an ATP molecule is formed from its component molecules

Answer 1

1. The ATP molecule i s a phosphorylated macromolecule
   Its composed of

Adenine- A nitrogen containing organic base

A ribose - A sugar molecule with a 5 carbon ring structure (pentose sugar) that acts as a backbone to which other parts are attached to

A chain of 3 Phosphates

aTP is synthesized(created) in a condensation reaction catalyzed by the enzyme aTP synthase releasing water molecule and joining ADP and Pi

Question 2

Suggest why human ATP synthase is not inhibited and bacterial synthase
is inhibited

Answer 2

Human ATP synthase has a different tertiary structure to
bacterial ATP synthase

Human ATP synthase has a different shape active site to
bacterial ATP synthase

Antibiotic cannot enter human cells/mitochondria

Antibiotic not complementary (to human ATP synthase);

Question 3

ATP is an energy source used in many cell processes. Give two ways in
which ATP is a suitable energy source for cells to use.

Answer 3

Releases relatively small amount of energy / little energy lost as
heat;
little danger of thermal death of
cells
2. Releases energy instantaneously;
energy is readily available
3. Phosphorylates other compounds, making them more reactive;
4. Can be rapidly re-synthesised;
5. Is not lost from / does not leave cells.

Question 4

Cells constantly hydrolyse ATP to provide energy.
(a) Describe how ATP is resynthesised in cells

Answer 4

From ADP and phosphate;

By ATP synthase;
3. During respiration/photosynthesis;

Question 5

(b) Give two ways in which the hydrolysis of ATP is used in cells.

Answer 5

To provide energy for other reactions/named process;

2. To add phosphate to other substances and make them more
   reactive/change their shape;

Question 6

Water is used to hydrolyse ATP.
Name the two products of ATP hydrolysis

Answer 6

Adenosine diphosphate and phosphate

Question 7

Hydrolysis of ATP is catalysed by the enzyme ATP hydrolase.
A student investigated the effect of ATP concentration on the activity of ATP
hydrolase. She used shortening of strips of muscle tissue caused by contraction
as evidence that ATP was being hydrolysed.
* She took four slides A, B, C and D, and added strips of muscle tissue of
the same length to each slide.
* She then added the same volume of ATP solutions of different
concentrations to the four slides and left each slide for five minutes.
* She then recorded the final length of each strip of muscle tissue

Other than those given, name two variables the student should have
controlled

Answer 7

1. Species / organism the muscle tissue came from;
2. Temperature of the muscle tissue / ATP solution / slides;
3. pH of the ATP solution;

Question 8

Describe and explain the pattern shown by the data in the table.

Answer 8

1. As concentration of ATP increases, length of muscle decreases
2. More ATP (hydrolysed by ATP hydrolase), so more energy
   released, so more muscle contraction / shortening of muscle;

Question 9

The new antibiotic is safe to use in humans because it does not inhibit the
ATP synthase found in human cells.
Suggest why human ATP synthase is not inhibited and bacterial synthase
is inhibited

Answer 9

Human ATP synthase has a different tertiary structure to
bacterial ATP synthase

Human ATP synthase has a different shape active site to
bacterial ATP synthase

Antibiotic cannot enter human cells/mitochondria

Antibiotic not complementary (to human ATP synthase);

Question 10

ATP is an energy source used in many cell processes. Give two ways in
which ATP is a suitable energy source for cells to use.

Answer 10

1. Releases relatively small amount of energy / little energy lost as
   heat;
2. Releases energy instantaneously;
3. Phosphorylates other compounds, making them more reactive;
4. Can be rapidly re-synthesised;
5. Is not lost from / does not leave cell

Question 11

Cells constantly hydrolyse ATP to provide energy.
(a) Describe how ATP is resynthesised in cells.

Answer 11

1. From ADP and phosphate;
2. By ATP synthase;
3. During respiration/photosynthesis;

Question 12

Give two ways in which the hydrolysis of ATP is used in cells

Answer 12

1. To provide energy for other reactions/named process;
2. To add phosphate to other substances and make them more
   reactive/change their shape;