Form 3 Chapter 1

Form 3 Science Chapter 1

FORM 3 CHAPTER 1 RESPIRATORY SYSTEM 1. Diagram 1 shows part of the human respiratory system.

P: ……………………………. S Q: ……………………………. S

R: ……………………………. Diagram 1 (a) Label P, Q and R on Diagram 1 with the following words. Lung

Diaphragm

Trachea [3 marks]

(b) The sequence shows the flow of inhaled air in the respiratory system. Trachea



Z



bronchiole



alveolus

Label Z on Diagram 1. [1 mark] (c) The movement of S causes the thoracic cavity to expand during inhalation. How does S move during inhalation? ……………………………………………………………………………………………………… [1 mark]

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Form 3 Science Chapter 1

2. Diagram 2 shows the gaseous exchange in an alveolus.

DIagram 2 (a) Identify the gases labelled P and Q. Gas P: …………………………………….. Gas Q: …………………………………………….. [2 marks] (b) Name the process involved in the gaseous exchange in the alveolus. ………………………………………………………………………………………………………. [1 mark] (c) What causes gas P to diffuse into the bloodstream? ………………………………………………………………………………………………………. ………………………………………………………………………………………………………. [1 mark] (d) What happens to gas P as it enters the blood capillary? ………………………………………………………………………………………………………. [1 mark] (e) State one difference between blood X and blood Y. ………………………………………………………………………………………………………. ……………………………………………………………………………………………………….

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Form 3 Science Chapter 1

[1 mark] 3. Diagram 3 shows a model of the respiratory system.

Stopper Glass tube

Balloon

Rubber sheet Diagram 3 (a) What do the balloon and rubber sheet represent? (i)

Balloon: ………………………………………………………………………………… ……

(ii)

Rubber sheet: ………………………………………………………………………… ……. [2 marks]

(b) (i) What happens when the rubber sheet is pulled downwards? …………………………………………………………………………………………………… [1 mark] (ii) Explain your answer in (b). …………………………………………………………………………………………… ……… …………………………………………………………………………………………………… [2 marks] (c) Name the process that is shown by activity (b)(i). ………………………………………………………………………………………………………

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Form 3 Science Chapter 1

[1 mark] 4. Diagram 4 shows an activity to show the effect of cigarette smoke on the lungs.

Diagram 4 (a) What are the changes to the following at the end of the activity? (i)

The temperature: ………………………………………………………………………… ….

(ii) The white cotton wool: ………………………………………………………………………. (iii)

The hydrogen carbonate indicator: …………………………………………………… …… [3 marks]

(b) State one inference based on the observation in (a)(iii). ……………………………………………………………………………………………………… [1 mark] (c) Name one harmful substance found in cigarette smoke. ……………………………………………………………………………………………………… [1 mark] (d) Suggest one good habit that can help to improve the quality of air around us. ………………………………………………………………………………………………………

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Form 3 Science Chapter 1

[1 mark]

5. Diagram 5 shows a process that takes place in the human respiratory system.

Diagram 5 (a) Name the process shown in Diagram 5. …………………………………………………………………………………………………… [1 mark] (b) Describe the movement of the following parts during this process. (i)

Ribs: ……………………………………………………………………………………… ….

(ii)

Diaphragm: ……………………………………………………………………………… …. [2 marks]

(c) Explain briefly how air is forced into the lungs. ……………………………………………………………………………………………………… ……………………………………………………………………………………………………… [2 marks] (d) Complete the sequence to show the flow of air into the lungs during this process. Nasal cavity

Bronchus

142 Alveolus

Form 3 Science Chapter 1

[2 marks]

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