Practise HL questions by analysing how negative feedback damps deviations in predator–prey and atmospheric systems, then evaluating stability and restoration.
Explain how predation may lead to:
stability in a population of the prey species.
as population of prey increases, more food is available for predators;
this leads to increase of predator population;
...so there is more predation / so prey population decreases; ...leading to cyclical changes around a stable equilibrium;
this is negative feedback / density dependent mechanism;
These marks can be awarded for appropriately annotated diagram, clearly demonstrating the marking points.
Answers that incorporate good/strong examples can help the student gain marks for Eol.
Marking guidance:
Do not award marks for just giving examples in this question.