Be precise with measurements, especially with syringes and pipettes. Label diagrams clearly: Use thin, straight lines.
: Factors kept constant to ensure a fair test. Common ones include: Temperature : Use a thermostatically controlled water bath. pH : Use a buffer solution of a known concentration.
Hydrochloric acid + Heat, neutralize with Sodium Hydrogencarbonate, then run Benedict’s test Acid hydrolyzes glycosidic bonds into reducing monomers. Starch Iodine in Potassium Iodide solution Blue-Black color No heating required. A orange/brown result is negative. Lipids
Always follow safety protocols, especially when using toxic chemicals or sharp instruments. biology 9700 practical notes
Every measuring instrument has an inherent limitation. The uncertainty is usually half of the smallest graduation on the instrument.
Measure changes in mass, length, or the percentage of plasmolysed cells under a microscope.
Parallax error when reading volumes. Fix: Ensure eyes are level with the bottom of the meniscus. 4. High-Yield Exam Day Tips Be precise with measurements, especially with syringes and
3. Planning and Evaluation (Paper 5 - Planning, Analysis, and Evaluation)
The independent variable goes in the first column. Headings must include the unit after a slash (e.g., Temperature / °C ).
Biology 9700 practical paper (Paper 3) assesses experimental skills and investigations through two main types of tasks: laboratory experiments and microscopic observations. Common ones include: Temperature : Use a thermostatically
Detects peptide bonds. Pale blue indicates a negative result. 3. Quantitative Methodologies & Enzyme Kinetics
Never draw individual cells. Draw the boundaries of different tissues (e.g., xylem, phloem, epidermis). Use clear, single lines—no shading or "feathering."
Keep temperature constant using a thermostatically controlled water bath; keep pH stable using specific chemical buffer solutions. Osmosis & Water Potential ( ) Investigations
Grind leaves with propanone to extract fat-soluble pigments.
Cut identical cylinders of potato or onion tissue using a cork borer. Measure their initial mass or length. Immerse them in varying concentrations of sucrose or sodium chloride solutions for at least 30 minutes. Blot dry gently and remeasure.