Application Q

Question 1

It is known that:
* during respiration saturated fatty acids yield more energy than unsaturated fatty acids
* saturated fatty acids have higher melting points than unsaturated fatty acids
* lipases in seeds act more rapidly on liquid substrates.
Use this information to show how each population is better adapted for its natural environment when compared with the other population. [4 marks]

Answer 1

1. Population 1 grew longer roots in warm temperatures and population 2 grew longer roots in cool temperatures;
2. Standard deviations do not overlap so difference (in mean) unlikely to be/not due to chance;
3. Population 1 (is better adapted to warm conditions because it) has more saturated fatty acids so more energy available (and more growth);
4. Population 2 (is better adapted to cool conditions because it) has more unsaturated/liquid fatty acids so more lipase activity (and more growth);

Question 2

How would you advise the student to use her calculated ratios to determine the water potential of the eggs

Answer 2

• Plot a calibration curve
• Interpolate from 1
• Change concentration to water potential