Biology 9700/31 May June 2009 | Cambridge AS Level Past Papers With Mark Scheme

1. Yeast enzyme activity investigation: effects of ethanol concentration on CO\\(_2\\) production measured using pH changes with Universal Indicator paper.

2. Temperature influence on yeast enzymes: bubble count data analyzed, graphical interpretation of enzyme activity trends, and control of experimental accuracy.

3. Graph plotting enzyme activity vs. temperature: estimation of activity at intermediate temperatures like 25°C using interpolation.

4. Plant vascular tissue analysis: plan diagrams of phloem and xylem bundles in transverse sections and detailed structural comparisons under high magnification.

5. High-power microscopy: measurement of root cell dimensions, preparation of labeled drawings, and comparison of transverse and longitudinal sections.

6. Differences in cell morphology: root transverse sections analyzed for structural and functional variability across specimens.