Key Stage 3 (KS3) · Science

Gas Exchange Systems: Practice Questions

5 multiple-choice questions marked as you go, and 5 written questions with worked solutions. All on Gas Exchange Systems.

10 questions26 marksFree, no account

Question 1

1 mark

What is the primary function of the mucus produced by the cells lining the breathing tracks?

Question 2

1 mark

During the process of inhalation, several mechanical changes occur simultaneously in the thoracic cavity. Which of the following correctly describes the state of the diaphragm and the air pressure relative to the atmospheric pressure?

Question 3

1 mark

Compare the air inhaled with the air exhaled by a human. Which of the following sets of data correctly represents the typical change in percentage composition of the major gases involved?

Question 4

1 mark

Which of the following describes the correct order of the components of the human gas exchange system as air is inhaled?

Question 5

1 mark

In the human gas exchange system, what is the specific function of the cilia found in the lining of the trachea?

Question 6

2 marks

Briefly describe the function of the alveoli within the human gas exchange system.

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Question 7

6 marks

In the Gas Exchange System, the alveoli possess specific structural adaptations to maximize the rate of diffusion. Identify three such features and explain how the concentration gradient is maintained by the circulatory system.

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Question 8

2 marks

In the study of Gas Exchange Systems, what is the name of the muscle located at the base of the chest that contracts and flattens during inhalation?

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Question 9

3 marks

The human Gas Exchange Systems are essential for supplying oxygen to the body.

(a) Describe the process of inhalation in terms of the movement of the diaphragm and the ribcage. (2 marks)
(b) Explain how the change in volume of the thoracic cavity leads to air entering the lungs. (1 mark)

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Question 10

8 marks

In the human gas exchange system, oxygen must travel from the atmosphere to the blood.

(a) Trace the path of an oxygen molecule from the trachea to the alveoli. (2 marks)
(b) The alveoli are highly adapted for efficient gas exchange. Explain how the following three features facilitate this process: surface area, diffusion distance, and concentration gradient maintained by blood flow. (3 marks)
(c) Explain the mechanism of inhalation in terms of the movement of the diaphragm, the external intercostal muscles, and the resulting changes in thoracic volume and pressure. (3 marks)

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