Biology 9700/51 May June 2015 | Cambridge AS Level Past Papers With Mark Scheme

1. Determining protease subtilisin A concentration using gelatin-coated simulated lenses and observing removal rates.
2. Effect of different subtilisin A concentrations on protein hydrolysis, focusing on cleaning efficiency.
3. Investigating prenatal alcohol exposure on nerve conduction speed in sensory and motor neurons of newborns.
4. Comparing conduction velocity changes at 20 and 400 days after birth in exposed versus non-exposed groups.
5. Using t-test for assessing the significance of differences in sensory nerve conduction speeds.
6. Validity concerns due to limited sample diversity and varying maternal alcohol consumption levels.