363 exam-style questions on Unity and diversity with answers and explanations. Six real samples below — the full set is free with an account.
Which structure is present in a plant cell but NOT in a typical animal cell?
Answer: cell wall
A cellulose cell wall (plus chloroplasts and a large permanent vacuole) is characteristic of plant cells; the others are common to both.
A cell is 50 µm across. In a drawing it measures 50 mm. What is the magnification of the drawing?
Answer: ×1000
Magnification = image size / actual size = 50 mm / 50 µm = 50 000 µm / 50 µm = ×1000.
Which organelle is the site of protein synthesis?
Answer: ribosome
Ribosomes assemble polypeptides during translation; the Golgi later modifies and packages proteins.
A defining property of a stem cell is that it
Answer: can self-renew and differentiate
Stem cells retain the capacity to divide (self-renew) and to differentiate; potency varies (totipotent, pluripotent, multipotent).
Which pair of bases forms three hydrogen bonds in DNA?
Answer: guanine and cytosine
G–C pairs form three hydrogen bonds; A–T pairs form two. More G–C content therefore raises DNA stability.
Which of the following provides evidence for evolution?
Answer: homologous structures
Homologous structures (same basic plan, different function) suggest common ancestry; other evidence includes fossils and molecular sequences.
That was 6 of 363 Unity and diversity questions.
Practise all 363 freeA student writes that water is 'the universal solvent'.
See the correction →StateAO1 · 1–2 marks
One word or one short sentence. No explanation, no working: the mark is for the fact itself.
OutlineAO2 · 1–4 marks
A brief account or summary: the main points in two or three sentences, no evaluation.
ExplainAO3 · 3–8 marks
Give reasons or causes: say what happens AND why, linking each step with 'because' or 'so that'.
363 Unity and diversity questions — free with an account. Spaced repetition, streaks and full exam simulations included.
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