Biology 9700/51 May June 2019 | Cambridge AS Level Past Papers With Mark Scheme

1. Measurement and calculation of reaction times using a ruler drop experiment, with analysis of the effect of height and background noise on reaction time.

2. Design of experiments to investigate background noise impact, including identifying dependent variables and establishing methods for controlled testing.

3. Bar chart suitability for data visualization, application of t-tests for statistical significance, and formulation of null hypotheses.

4. Analysis of task repetition impact on task accuracy, with independent and dependent variables, and conclusions about external disruptions and prior experience on performance.

5. Calculation of horse semen sample volume and determination of required straws for insemination based on sperm cell count and insemination requirements.

6. Use of a hemocytometer to estimate sperm concentration, including criteria for cell inclusion and explanation of cryoprotective solution components (sugar, buffer, antibiotics) for semen storage.