IB skill practice

Explain transport systems in animals and plants

Paper 1, Paper 2 5 marks Difficulty 4

Explain blood transport role

A circulation diagram in a Auckland physiology lesson shows red blood cells carrying oxygen from lungs to body cells. Explain why a transport system is needed in larger animals. Enter the answer and choose the interpretation that best matches the biological evidence.

Worked practice: biological evidence and answer

Use the labelled biological evidence first, then connect it to the final answer.