Equal areas of membrane at the thin centre and the thicker edge of a red blood cell are exposed to the same oxygen concentration. Which statement predicts how the region affects oxygen uptake and gives the correct reason?
Oxygen enters at the same rate in both regions because the cell contains no nucleus.
Oxygen enters more slowly at the thin centre because less haemoglobin is located beneath that region.
Oxygen enters more rapidly at the thin centre because it has a shorter distance to diffuse into the cell.
Oxygen enters more rapidly at the thicker edge because more cytoplasm lies beneath the membrane.
67 exam-style questions on Edexcel GCSE Biology 8.2 Blood and circulation, covering 8.2.1 Structure and function of the blood, 8.2.2 Structure of blood vessels, 8.2.3 Structure of the heart and circulatory system, and 8.2.4 Cardiac output. Each one has a worked solution and a mark scheme showing where the marks go.