This is the official Cambridge mark scheme for Biology (5090) Mark Scheme 2 (Variant 1) from the 2026 May-June session. Mark schemes show exactly how each mark is awarded, including acceptable alternative answers, required key terms, and common errors that lose marks. Cambridge mark schemes use notation like "allow," "accept," and "do not credit" to define the boundary between full marks and zero.
Also referenced as: 5090_s26_ms_21 · 5090/21/m/j/26 ms · 5090/21 May/June 2026 ms
Paper 2: Theory — This is Paper 2: Theory, worth 80 marks with a duration of 1h 45m. Structured and free-response questions. All questions are compulsory. Requires extended writing, data analysis, and application of biological knowledge.
This mark scheme corresponds to 5090_s26_qp_21. For maximum revision benefit, attempt the question paper under strict exam conditions first, then use this mark scheme to self-assess. Pay attention to the marking notation: "allow" means an alternative is accepted, "do not credit" means a specific phrasing is rejected even if technically correct, and "ORA" (or reverse argument) means the mark can also be earned with the opposite reasoning.
Cambridge mark schemes reward precise language. For Biology (5090), look for keywords the examiner requires — definitions must include specific terms (e.g., "per unit mass," "resultant"), and calculations must show working even if the final answer is correct. Understanding mark scheme conventions helps you write answers that hit every marking point, not just the general idea.
