Generated by claude-sonnet-4-6 · 2026-06-17 12:34 · grounding rag
Model Answer
Tooth enamel is made of a hard, mineralised substance. Bacteria acting on sugars produce acids that demineralise (soften) the enamel, leading to dental caries (tooth decay). Enamel is important because it forms the protective outer covering of teeth; once it is softened or destroyed, microorganisms can invade deeper layers, causing infection.
Source: Chapter 5, Section 5.2.4 — "More to Know: Dental Caries"
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Explanation
- The passage mentions enamel in the context of dental caries — it is demineralised by bacterial acids. The textbook does not explicitly state the chemical composition of enamel beyond calling it a hard mineralised layer, so do not over-specify.
- Examiners award 1 mark for stating what enamel is/does (hard protective covering, mineralised) and 1 mark for its importance (protects teeth; acid softens/demineralises it leading to decay and infection).
- Keep your answer focused on the passage; do not bring in outside chemistry (e.g., hydroxyapatite) unless taught in class.