Science — AI-generated practice question

Transport of Oxygen:
Oxygen is carried by the red blood corpuscles (RBCs), which contain haemoglobin. Haemoglobin binds with oxygen in the lungs and releases it to the body cells.

Transport of Carbon dioxide:
Carbon dioxide is transported in dissolved form in the plasma. It travels from body tissues to the lungs, where it is removed from the blood and expelled during exhalation.

Both substances are transported through the circulatory system consisting of the heart, blood, and blood vessels.

Source: Chapter 5, Section 5.4.1 – Transportation in Human Beings

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• Examiners expect students to clearly distinguish between how O₂ and CO₂ are transported — this is the core of the answer.
• Key point: O₂ → RBCs (haemoglobin); CO₂ → plasma (dissolved form). Both facts must appear to get full marks.
• Mentioning the circulatory system as the medium of transport adds completeness for a 3-mark answer.
• Do not confuse: CO₂ is not carried by RBCs in this context — the textbook specifically states plasma carries CO₂ in dissolved form.