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Specialised cells — red blood cells

GCSE · Combined Science · CCEA · B1.1Cells: animal, plant and bacterial cells; cell organelles; specialised cells

Question

Explain how red blood cells are adapted for their function of transporting oxygen around the body.

[4 marks]

Mark scheme — B1 per adaptation with explanation (up to B4):

  • Biconcave disc shape → large surface area relative to volume → more oxygen can be absorbed per cell (B1+B1).
  • No nucleus → more space in the cell for haemoglobin molecules → carries more oxygen (B1+B1).
  • Haemoglobin protein → binds oxygen easily at high concentrations (lungs) and releases it at low concentrations (tissues) (B1+B1).
  • Flexible cell membrane → can squeeze through narrow capillaries to deliver oxygen throughout the body (B1). Award any 4.

Total: 4 marks.

4 marks · take your time before peeking.

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Generated by TopMyGrade AI · cross-check official sources before relying on the mark-scheme phrasing.