Explanation : High temperatures denature the proteins embedded in the cell membrane and disrupt the phospholipid bilayer. This makes the cell membrane fully permeable, allowing the vacuolar red pigment (betalain) to leak out rapidly via diffusion.
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:
): High pigment release, intense red color. Membrane damaged, allowing pigment leakage. o level biology practical 2020 answers
Contamination between samples if syringes are not washed.
Alters enzyme activity, compromising the validity of the independent variable. Here’s how to use them effectively: ): High
The 2020 paper required candidates to manage their time efficiently across two main experimental tasks. The exam evaluated core syllabus areas, specifically:
If you are looking for specific past paper questions, I can help you find: The The 2020 Oct/Nov Paper 3/4 Alters enzyme activity, compromising the validity of the
Remained blue (>120s), indicating 0 concentration.
A staple of the O Level Practical is the low-power or high-power plan drawing of a biological specimen, such as a cross-section of a stem or leaf. :
: Students performed the Benedict’s test. Successful responses required a structured table with correct headings (e.g., sample name, time taken for color change, and final glucose concentration).
Understanding the structural breakdown and underlying scientific principles of past papers like the 2020 session is one of the most effective ways to prepare for upcoming practical examinations. Overview of the 2020 Biology Practical Exam