Respiration | Edexcel IGCSE Science (Double Award) (Modular): Biology Unit 1 Exam Questions & Answers 2024 [PDF]

1a

1 mark

Which of the following statements relating to respiration is not correct?

Respiration produces ATP
Respiration involves the breaking of bonds within biological molecules
Respiration occurs in animals but not in plants
Respiration releases energy in the form of heat

Choose your answer

1b

2 marks

The diagram shows an animal cell.

Diagram of an animal cell with four label lines lettered W to Z. W points to a small dark dot lying in the pale region of the cell, X points to the large dark rounded structure near the centre of the cell, Y points to one of several small oval structures in the pale region, and Z points to the pale region that fills the rest of the cell inside the cell membrane

(i) Identify the letter, from W-Z, that indicates the sub-cellular structure where respiration takes place.

[1]

(ii) Name the sub-cellular structure identified in part (i).

[1]

How did you do?

1c

4 marks

Complete the following sentence about respiration:

glucose chemical protein cell

muscle temperature nerve

Respiration releases energy from ............... . The energy released can be used in life processes such as ............... reactions, ............... contraction and maintaining a constant body ............... .

How did you do?

1d

6 marks

Complete the table with a (✓) or a (X) to show the products and reactants of aerobic respiration in animals.

	Product	Reactant
Oxygen
Carbon dioxide
Lactic acid
Glucose
Water
Ethanol

How did you do?

Was this exam question helpful?

3a

2 marks

The diagram shows some apparatus set up to investigate respiration in yeast cells. Note that paraffin is impermeable to oxygen.

Diagram of two stoppered test tubes joined by a delivery tube. Tube A on the left contains yeast cells in sugar solution with a layer of liquid paraffin floating on top of it. A delivery tube runs from the stopper of tube A across to tube B on the right, where it dips below the surface of the limewater and gas bubbles are rising from its open end

(i) State the type of respiration being investigated in this experiment.

[1]

(ii) State how you reached your answer to part (i).

[1]

How did you do?

3b

1 mark

Identify the gas in the bubbles produced by the yeast in part (a).

How did you do?

3c

2 marks

A group of students wanted to use the apparatus in part (a) to investigate the effect of temperature on respiration in yeast.

They set up the test tubes containing the yeast and sugar solution in water baths at a range of temperatures and counted the number of bubbles produced to give a measure of the rate of respiration.

Give two factors that the students would need to control in their investigation.

How did you do?

3d

4 marks

Complete the table to indicate whether the statements apply to aerobic respiration, anaerobic respiration or both.

The first statement has been completed for you.

Statement	Respiration Type
Produces lactic acid as a waste product	Anaerobic respiration
Produces ethanol when it occurs in yeast
Produces lots of ATP
Releases energy from glucose
Increases during intense exercise

How did you do?

Was this exam question helpful?

1a

1 mark

Which of these is the balanced chemical symbol equation for aerobic respiration?

$C_{6} H_{12} O_{6} + 6 O_{2} \to 6 {CO}_{2}$
$C_{6} H_{12} O_{6} \to 2 C_{2} H_{5} OH + 2 {CO}_{2}$
$C_{6} H_{12} O_{6} + 6 {CO}_{2} \to 6 O_{2} + 6 H_{2} O$
$C_{6} H_{12} O_{6} + 6 O_{2} \to 6 {CO}_{2} + 6 H_{2} O$

Choose your answer

1b

8 marks

A student uses this apparatus to investigate aerobic respiration in a locust.

Diagram of a respirometer. A locust sits at the bottom of a conical flask that is sealed by a bung. A small square of filter paper, labelled as being soaked in a liquid to absorb carbon dioxide, hangs from the bung inside the flask. A syringe and a bent glass tube also pass down through the bung. The glass tube leads out to a horizontal capillary tube mounted alongside a scale, and a coloured water drop sits inside the capillary tube

(i) The coloured water drop moves during the investigation.

Explain why the coloured water drop moves during the investigation.

[2]

(ii) The student compares the aerobic respiration of male and female locusts.

He uses three male locusts and three female locusts.

He uses locusts of the same age and the same species.

Explain three other variables that the student needs to control.

[6]

How did you do?

1c

4 marks

The table shows the student's results.

	Distance moved by coloured water drop in mm
	Male	Female
Trial 1	5.0	5.4
Trial 2	4.9	5.2
Trial 3	2.0	5.2
Mean	5.0

(i) Complete the table by giving the missing mean value.

[1]

(ii) Comment on the reliability of the data in the table.

[2]

How did you do?

Was this exam question helpful?

3a

3 marks

In the absence of sufficient oxygen, cells respire anaerobically.

Describe the similarities and differences between anaerobic respiration in the muscle cell of an animal and anaerobic respiration in a yeast cell.

How did you do?

3b

2 marks

A student used the equipment shown in the diagram to investigate the rate of anaerobic respiration in yeast.

The student measured the volume of carbon dioxide produced by 5 g of yeast over a 60 minute period. His results are shown in the table below.

Time / minutes	Total volume of gas collected / cm³
10	0.5
20	0.7
30	1.6
40	2.8
50	5.9
60	6.3

Rate can be calculated using the following equation:

$Rate = \frac{Volume of product produced}{Time}$

Use the equation to calculate the average rate of carbon dioxide production per minute between 30 and 60 minutes in the investigation.

How did you do?

3c

3 marks

Suggest why the rate of carbon dioxide production shown in part (b) decreased between 50 and 60 minutes.

How did you do?

3d

2 marks

Explain how the student could have ensured the reliability of the results.

How did you do?

Was this exam question helpful?

1a

2 marks

Write the balanced symbol equation for respiration.

How did you do?

1b

3 marks

Some scientists wanted to investigate respiration rates in different areas of a plant.

They measured carbon dioxide production in the roots and leaves of a plant at night time.

The table shows the rate of carbon dioxide production that they measured.

Part of the plant	Mean rate of carbon dioxide production / cm³m^-2s^-1
Leaves	0.042
Root	0.056

Calculate the percentage difference in carbon dioxide production in the leaves compared to the roots.

How did you do?

1c

3 marks

The carbon dioxide readings shown in the table in part (b) were all taken during the night time.

Suggest a reason for this.

How did you do?

1d

2 marks

Suggest an explanation for the results shown in the table in part (b).

How did you do?

1e

1 mark

In order to collect the data about carbon dioxide produced by the roots of the plant, scientists took samples of the air from the soil around the plant roots and adjusted it to account for atmospheric carbon dioxide levels.

Suggest why the readings they took may still be higher than the actual rate of carbon dioxide production in the plant roots.

How did you do?

Was this exam question helpful?

Respiration (Edexcel IGCSE Science (Double Award) (Modular): Biology Unit 1): Exam Questions