Work through the list without notes. If you cannot do a statement, follow its link, then come back. Guide = study guide; Practice = practice questions.
Understanding
- I can define an adaptation and explain why it gives an advantage only in a particular environment. (Guide: “Adaptations come from variation that already exists”; Practice Q1)
- I can explain why mutations are not caused by the environment, and describe how a new selective pressure changes allele frequencies. (Guide: “Variation meets a changing environment”; Practice Q1)
- I can define heterozygote advantage and identify it from relative fitness values. (Guide: “Heterozygote advantage”; Practice Q2)
- I can explain how an invasive species spreads and harms native species, using one real example. (Guide: “Invasive species”; Practice Q3)
- I can describe how logging, urbanisation, monocropping, introduced diseases and climate change disrupt ecosystems and can cause extinctions. (Guide: “Human activities speed up change”)
- I can explain how a geological or meteorological event, such as El Niño, continental drift or a meteor impact, changes habitats and species distributions. (Guide: “Geological and meteorological events”; Practice Q7)
Calculation and skills
- I can calculate concentration factors along a food chain and explain biomagnification. (Guide: Worked example 1, Figure 1; Practice Q4)
- I can read a logarithmic axis, where each grid line is ten times the one below. (Guide: Figure 1)
- I can calculate a percentage change and a mean from ecological data. (Practice Q5, Q7)
- I can carry out a chi-square test: null hypothesis, expected counts, χ², degrees of freedom and critical value. (Guide: Worked example 2; Practice Q6)
Reasoning
- I can explain the full chain of eutrophication, including why oxygen falls after the algal bloom peaks. (Guide: Figure 2; Practice Q5)
- I can state a conclusion as “reject” or “fail to reject” the null hypothesis, and say what the test does and does not show. (Guide: Worked example 2; Practice Q6)
- I can predict the effect of a disruption on a population and explain why low genetic diversity raises the risk of extinction. (Practice Q7)
All ticked? This is the last topic of the course. Return to the course roadmap to plan your review, and revisit Biodiversity to link resilience with the disruptions on this page.