AS & A Level Biology (9700) — May–June 2025, Paper 21
6 questions · every question answerable online with instant point-by-point AI marking against the official mark scheme.
Start with Question 1 →Amylose and the triglyceride stearin are macromolecules. Explain why amylose and stearin are macromolecules, but only amylose is a polymer.
Answer this question and get it marked →In mammals, the small intestine is the main site of absorption of the products of digestion. Fig. 2.1 is a transmission electron micrograph (×12500) of a longitudinal section of…
Answer this question and get it marked →Scientists investigated the progress of reactions catalysed by two enzymes: dopa oxidase and neutrase. The reactions are shown in Fig. 3.1. Fig. 3.2 shows the progress of the…
Answer this question and get it marked →Cells of the immune system have cell surface receptors that detect molecules made by pathogens. One of these cell surface receptors is known as TLR8. The gene TLR8 is found on the…
Answer this question and get it marked →Phosphate ions are absorbed from the soil solution by roots and are needed for cellular processes throughout plants. Scientists investigated the movement of phosphate ions in…
Answer this question and get it marked →Fig. 6.1 is a ribbon model of a molecule of haemoglobin. State the part of the haemoglobin molecule labelled X.
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