Biology 9700,51 Oct Nov 2024 | Cambridge AS - A Level Past Papers With Mark Scheme

1. Photosynthetic Pigments & Chromatography | Pigment Identification and Rf Value Calculation – Determining Rf values, identifying pigments present in different algae species, and comparing photosynthetic pigment composition.

2. Absorption Spectra & Photosynthesis | Light Wavelength and Algal Growth Comparison – Analyzing absorption spectra data, predicting photosynthetic efficiency under different light conditions, and comparing species′ responses to blue, green, and red light.

3. Experimental Design & Investigation | Measuring Photosynthesis Using Algal Beads – Planning a valid investigation, using pH as an indirect photosynthesis indicator, and ensuring controlled conditions with colorimetric analysis.

4. Statistical Testing & Data Analysis | Using the t-test for Hypothesis Testing – Justifying the use of the t-test, stating null hypotheses, and comparing species′ photosynthetic rates statistically.

5. Biodiversity Indices & Ecological Sampling | Simpson’s and Shannon Index Interpretation – Evaluating biodiversity differences using multiple indices, identifying data factors affecting results, and making ecosystem comparisons.

6. Sampling Techniques & Representation | Improving Ecological Sampling for Accuracy – Enhancing sampling strategies for invertebrates, adjusting spatial and temporal data collection, and refining quadrat-based methods for reliability.