Biology 9700/33 May June 2019 | Cambridge AS Level Past Papers With Mark Scheme

1. Serial dilution preparation for protein concentration assessment in milk using potassium hydroxide and copper sulfate solutions.

2. Protein content analysis in unknown milk samples by colorimetric comparison with serially diluted standards.

3. Bar chart representation of protein percentages in milk from different mammals, highlighting buffalo, camel, horse, goat, and sheep.

4. Enzymatic activity of pepsin across varying pH levels, identifying optimal conditions for protein breakdown.

5. Microscopic examination of plant stem and root transverse sections, focusing on tissue structure, labeling epidermis, and comparing observable differences.

6. Measurement of actual root width from photomicrographs using scale bars and detailed calculations.