3.1 Diffusion in unicellular organisms
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How does oxygen enter an Amoeba?
(1)Total for this question: 1 mark
3(h) TRANSPORT · EXAM QUESTIONS
3.1 Diffusion in unicellular organisms
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3.1 Diffusion in unicellular organisms
Exam question
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Explain why a unicellular organism such as Paramecium does not need a transport system.
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Total for this question: 2 marks
3.1 Diffusion in unicellular organisms
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A spherical single-celled organism has a surface area of 300 µm² and a volume of 500 µm³. Calculate its surface area to volume ratio.
(2):1Total for this question: 2 marks
3.1 Diffusion in unicellular organisms
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Explain why bacteria living in water can obtain all the oxygen they need by diffusion.
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Total for this question: 2 marks
3.1 Diffusion in unicellular organisms
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Illustrative context: free-living flatworms in ponds.
Some flatworms are large but very thin and flat. Suggest how this body shape lets them survive without a blood system.
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Total for this question: 2 marks
3.1 Diffusion in unicellular organisms
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As a cube-shaped cell gets larger, what happens to its surface area to volume ratio?
(1)Total for this question: 1 mark
3.1 Diffusion in unicellular organisms
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Describe how carbon dioxide leaves a single-celled organism.
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Total for this question: 2 marks
3.1 Diffusion in unicellular organisms
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Compare how oxygen reaches the mitochondria in an Amoeba and in a human muscle cell.
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Total for this question: 2 marks