BreathingOxford AQA IGCSE Biology: Subtopic test

1. 1
   A doctor is listening to a patient's chest with a stethoscope after the patient recovered from a bout of bronchitis, explaining how the lungs work.

   (a)

   Which structures branch from the trachea and lead into the lungs?

   [1 mark]

   • ABronchi
   • BAlveoli
   • CDiaphragm
   • DOesophagus

   (b)

   Which structure moves downward and flattens during inhalation, increasing the volume of the thorax?

   [1 mark]

   • AAlveoli
   • BRibs
   • CTrachea
   • DDiaphragm

   (c)

   Describe the changes in volume and pressure inside the thorax during inhalation that cause air to enter the lungs.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A class carries out an experiment using limewater to compare the composition of inhaled air with exhaled air breathed out through a straw.

   (a)

   Which gas is present in a higher percentage in exhaled air compared with inhaled air?

   [1 mark]

   • AOxygen
   • BCarbon dioxide
   • CNitrogen
   • DArgon

   (b)

   Which gas has a lower percentage in exhaled air compared with inhaled air?

   [1 mark]

   • ACarbon dioxide
   • BWater vapour
   • COxygen
   • DNitrogen

   (c)

   Explain why exhaled air contains more water vapour than inhaled air.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A public health campaign is producing information leaflets to explain to smokers how long-term smoking affects the lungs and airways.

   (a)

   Describe three ways in which smoking damages the human respiratory system.

   [3 marks]

   (b)

   Explain how long-term smoking increases the risk of lung cancer and emphysema, referring to tar and damage to the alveoli.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A group of trainee paramedics is being taught how the human respiratory system is structured and how breathing brings air into contact with the blood.

   (a)

   Describe the structure of the alveoli and explain how they are adapted for efficient gas exchange.

   [6 marks]

   (b)

   Describe the structures of the human respiratory system and explain the mechanism of breathing, including the roles of the diaphragm and intercostal muscles.

   [6 marks]

   Total for question 4: 12 marks

End of questions