Answering Short & Structured Questions (Copy)
Answering Short & Structured Questions – Expanded Section (O Level & IGCSE Biology Alternate to Practical)
1. Understanding the Question Type
Short and structured questions typically:
- Have specific mark allocations (e.g. [2], [3])
- Require clear, direct, factual answers
- Often test observation, explanation, method, or analysis
- May use data, diagrams, graphs, or experiments as stimulus
2. Key Command Words and What They Require
| Command Word | What to Do |
|---|---|
| State | Give a brief, direct answer – no explanation needed |
| Describe | Say what happens/what is seen, using full sentences and exact observations |
| Explain | Say why it happens – link cause to effect using correct biology |
| Suggest | Apply biological understanding to a new context – not always in syllabus |
| Compare | State similarities and differences clearly – use both sets of data |
| Calculate | Show formula, substitute values, give final answer with correct unit |
3. Structure for Different Question Types
A. Observation-Based Questions
- Use data, table, or diagram to support your answer.
- Always state what changed and by how much.
Example:
“Describe what happens to the mass of the potato strip in 0.8 mol/dm³ sugar solution.”
Answer:
“The mass decreases from 5.2 g to 4.4 g, a loss of 0.8 g.”
B. Data Interpretation
- Identify trend, optimum, anomalies
- Quote actual values for full marks
Example:
“What is the optimum pH for this enzyme?”
Answer:
“The optimum pH is 7, as the time taken for starch to be broken down is shortest at this pH.”
C. Biological Explanation
- Use scientific terms: active site, denatured, osmosis, concentration gradient, etc.
- Link cause to effect clearly in 2 parts.
Example:
“Explain why no bubbles are produced at 90°C in the enzyme experiment.”
Answer:
“At 90°C, the enzyme becomes denatured. Its active site changes shape and can no longer catalyze the reaction.”
D. Control Questions
- State what a control is missing and why it is used.
Example:
“Why was boiled enzyme used in this experiment?”
Answer:
“To show that the reaction is due to the enzyme. Boiled enzyme is denatured and will not break down the substrate.”
E. Design & Method Questions
- Use clear step-by-step, bullet or numbered format if possible.
- Include equipment, measurements, timing, and variables.
Example:
“Describe how you would investigate the effect of light on germination.”
Answer:
- Place seeds in two petri dishes with damp cotton.
- Keep one dish in light, the other in darkness.
- Keep temperature and water the same for both.
- Observe number of seeds germinated after 5 days.
- Repeat for reliability.
F. Table Completion / Matching / Labeling
- Write clearly and exactly what is asked.
- Use correct spellings and standard biological terms.
Example:
“Label part A of the leaf section shown.”
Answer:
“Palisade mesophyll”
4. Examiner Expectations for Full Marks
| Marks | Requirement |
|---|---|
| 1 mark | Correct key fact or value, no explanation needed |
| 2 marks | Fact + explanation or two distinct points |
| 3 marks | Sequence (e.g., method), trend + explanation, or comparison of two data sets |
| 4+ marks | Requires structure: steps, reasoning, calculations, or extended explanations |
5. Tips for Success
- Always read the marks – they tell you how many points to make
- Use short, complete sentences — no bullet points unless asked
- Never leave a question blank — guess if unsure, especially with data
- Quote units and numerical values where applicable
- Don’t restate the question — get straight to the point
6. Common Pitfalls to Avoid
- Vague terms: “it changed,” “it did something”
- Forgetting units or giving wrong units
- Giving description when explanation is asked
- Writing too much — stay within the marks given
- Not referring to data when required