O Level Biology Practical 2020 Answers

Most O Level Biology practical exams in 2020 tested these three core areas:

Ensure constant volumes of Benedict's solution and urine sample across all tubes. Read syringes at to avoid parallax error. Question 2: Biological Drawing & Measurement

The official 2020 mark schemes are more than just answer keys; they are a roadmap to exam success. Here’s how to use them effectively:

This comprehensive guide breaks down the core experiments from the 2020 sessions, details the suggested answers, and highlights key practical skills to help you secure a distinction. Core Experiments and Suggested Answers from 2020

It explains why students lost marks. For example, it might say, "Many candidates failed to mention that the Benedict's solution needed to be heated." This provides insight that a simple "Answer: Glucose" list cannot. o level biology practical 2020 answers

: Contained the highest glucose concentration (~0.95 ), showing the fastest time to change colour (approx. 26s). Sample D : Contained no glucose ( ), remaining blue even after 120s of heating. Samples A & E : Had identical concentrations (~0.62 ) and similar reaction times (approx. 34s). Accuracy Improvements:

The factor you change deliberately (e.g., testing at 20°C, 30°C, 40°C, 50°C, and 60°C using regulated water baths).

While this article reconstructs the , you should verify with official sources:

Rate of transpiration increases with temperature, air movement, and light intensity; decreases in high humidity. Most O Level Biology practical exams in 2020

Water enters the plant cells via osmosis across a partially permeable membrane. Cells become turgid, resulting in an increase in the length, mass, and flexibility of the tissue strip.

) for points and a smooth line of best fit or ruled straight lines as instructed. . Always show working and include the " Accuracy

It improves the of the results by minimizing the effect of anomalies or outliers.

Your recorded pH values must be consistent with the treatments. Slice A was dipped in HCl, so a low pH (acidic) is expected. Slice C is an untreated banana, which has a neutral pH. Inconsistent readings would indicate a procedural error and cost you marks. Here’s how to use them effectively: This comprehensive

Testing a variegated leaf for starch using the iodine test.

Measure the same length on the actual specimen or reference photograph.

The experiment involved three treatments: a banana slice dipped in to lower the pH, a slice cut into small pieces to increase surface area, and an untreated slice as a control.

In this core plant physiology experiment, students investigated how temperature affects the release of red pigment from beetroot tissue.

The you want to verify against the marking scheme