Biology 9700/33 Oct Nov 2020 | Cambridge AS Level Past Papers With Mark Scheme

- Yeast cell enzyme activity, sugar breakdown, carbon dioxide release, carbonic acid formation.
- Indicator color change, measurement of reaction time, proportional dilution of yeast suspension.
- Risk assessment of experimental procedure, safety precautions, use of hydrogencarbonate indicator.
- Temperature effects on enzyme activity, immobilization of yeast cells in alginate beads, carbon dioxide collection.
- Graph plotting of experimental data, analysis of trends, explanation of graph shape.
- Observable differences in plant stem tissues, drawing and labeling of cellular structures, accuracy in measurements.