Biology Unit 1 Booklet 1 Flashcards
Critically analysing data on disease e.g. Drinking excessive alcohol CAUSES breast cancer… (2)
An established correlation is not the same as a causal link (1)
Other factors may be involved e.g. Temperature (1)
What is correlation? (1)
When a change in one or two variable is reflected by a change in the other variable. (1)
Define risk in terms of health (1)
A measure of the probability that damage to health will occur as a result of a given hazard. (1)
What is the purpose of a control experiment? (1)
To ensure that any change in the results is due to the changing (independent) variable and nothing else. (1)
How to set up a control experiment (2)
Remove the factor that is being changed e.g. Placebo drug or for an enzyme reaction either a denature enzyme or distilled water should be used. (1)
Keep everything else the same. (1)
Advantage of expressing results as a ratio (2)
Allows comparison. (1)
As they have different values. (1)
How to improve reliability of results. (2)
Allows anomalies to be identified (1)
Allows calculation of a more reliable mean. (1)
How taking additional readings can improve a graph. (2)
Line of best fit may be more reliable. (1)
Point where the line crosses may be more reliable. (1)
Error bars could be plotted. (1)
To show variability about the mean. (1)
Standard deviation (2)
The biggest value plus or minus mean, the greater the standard deviation so the more variation there is in the data. (1)
The smaller the value plus or minus mean, the lower the standard deviation so the less variation there is in the data. (1)
Points to consider for evaluation questions (how science works) (6)
Sample size- may not be representative. (1)
Repeats- identifying anomalies may be hard. (1)
Scientists may have vested interest to present results in a biased way. (1)
Results may not have been peer reviewed by other scientists. (1)
Experiment relating to human disease may have not been carried out on humans. (1)
A control experiment may not have been carried out. (1)
Suggest why certain protein/enzyme dugs cannot be taken orally (1)
Proteins may be digested/ broken down by enzymes (1)
Protein may be denatured by the stomach acid (1)
Calculating percentage increase (1)
((Original value➖new value) ➗new value)✖100
Calculating percentage decrease (1)
((Original value➖new value) ➗ original value) ✖100
