Biology 5090 · O Level · Human gas exchange

Human gas exchange — practice question

The diagram illustrates the rib cage and some of the muscles used in breathing, viewed from the side. What occurs when the intercostal muscles shown in the diagram contract?

  • AThe diaphragm moves down.
  • BThe lungs inflate.
  • CThe pressure inside the lungs decreases.
  • DThe ribs move down.

Worked solution & mark scheme

This 1-mark question has a full step-by-step worked solution and mark scheme.

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI