Biology (9610) 考试技巧

计算器程序

常见错误

1. 1high涉及分数: 2Living organisms vary

   Writing that standard deviations or standard errors 'overlap' as statistical proof, without explicitly stating the biological/statistical conclusion.

   如何避免: Always follow up the observation of overlapping standard deviations by stating: 'Therefore, there is no statistically significant difference between the means.'
2. 2high涉及分数: 3Cells and cell structure

   Failing to convert units (e.g. millimetres to micrometres) before performing magnification or cell size calculations.

   如何避免: Convert measurements taken with your ruler (in mm) to micrometres (μm) by multiplying by 1,000 before dividing by the real length of the cell or the scale bar value.
3. 3medium涉及分数: 2Respiration

   In respirometer questions, omitting the requirement of maintaining a constant temperature.

   如何避免: Always state that the respirometer must be kept in a thermostatically-controlled water bath because temperature fluctuations alter gas volume and pressure, affecting the readings.
4. 4medium涉及分数: 1Mass transport systems in plants

   Failing to cut the plant stem underwater when setting up a potometer.

   如何避免: Specify that the stem must be cut underwater to prevent air bubbles from entering the xylem and creating air locks that block water transport.
5. 5medium涉及分数: 2The diversity of living organisms

   In chromatography, drawing the starting line in ink or placing the line below the solvent level.

   如何避免: Always draw the starting line in pencil (as graphite is insoluble) and ensure it sits above the solvent level so the pigments do not dissolve directly into the solvent reservoir.
6. 6high涉及分数: 1Respiration

   Stating that respiration 'produces energy' or 'creates energy' in essay responses.

   如何避免: Use accurate scientific terminology: respiration releases energy to generate ATP, or couples metabolic reactions to produce ATP.
7. 7medium涉及分数: 1Gas exchange and the transport of oxygen in living organisms

   Referring to competitive inhibitors of haemoglobin (like carbon monoxide) binding to the 'active site'.

   如何避免: Haemoglobin is a transport protein, not an enzyme. Clarify that carbon monoxide binds to the haem/oxygen-binding sites, not an active site.
8. 8medium涉及分数: 2Inheritance

   In genetic cross diagrams, failing to associate offspring genotypes with their corresponding phenotypes.

   如何避免: Always write down the phenotype underneath every single genotype in your Punnett square/diagram, and write the final phenotypic ratio clearly.