Explain how carbon atoms present in the carbon dioxide in the atmosphere become part of the body of a fox.

Eduqas GCSE Biology — 6.2 The principle of material cycling · Explain · 4 marks · View as Markdown

Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).

Model answer (4 marks)

Plants absorb CO₂ from the atmosphere during photosynthesis, converting it into glucose and other carbohydrates.
The fox consumes an animal that has eaten these plants (e.g. a herbivore).
The carbon‑containing molecules are digested and incorporated into the fox’s body tissues, forming its own organic molecules.

Examiner tips

Use the word ‘absorb’ for plants and ‘consume’ for the fox. Show the flow: CO₂ → plant → herbivore → fox. Mention digestion and incorporation into tissues.
Use the exact terminology: photosynthesis, glucose, carbohydrates, digestion, body tissues.

Common mistakes

Confusing the fox eating plants directly. Omitting the step that the fox eats a plant‑eating animal. Using vague terms like ‘food’ instead of ‘organisms’ or ‘tissues’.

Mark scheme (4 marks)

Plants absorb carbon dioxide from the atmosphere during photosynthesis
Carbon dioxide is converted into organic molecules / glucose / carbohydrates in the plant
The fox eats an animal that has eaten the plant (accept: the fox eats a plant-eating animal / prey that fed on plants)
The carbon-containing molecules are digested and used to build the fox's own body tissues / organic molecules

Key terms in this question

carbon dioxide