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 state the three course dates (4.6, 3.9 and 3.5 bya) and say what each one tells me about the origin of life. (Guide: “Geological evidence”; Practice Q1)
- I can explain why fossils give a minimum age for life and why the hostile period limits the earliest plausible date. (Guide: Figure 1; Practice Q1, Q4)
- I can describe what a stromatolite is and why it counts as evidence of early life. (Guide: “Geological evidence”; Practice Q5)
- I can describe the RNA world hypothesis and state its three assumptions in my own words. (Guide: “The three assumptions”; Practice Q3)
- I can explain why RNA, unlike DNA or protein alone, could be both genetic material and catalyst. (Guide: Figure 2; Practice Q7)
Skills
- I can calculate time spans from the course dates and scale them onto a model timeline. (Guide: Worked example 1; Practice Q4)
- I can state a null hypothesis for an experiment on RNA catalysis. (Guide: Worked example 2; Practice Q6)
- I can predict the results of control tubes (RNase, protease, no template, mismatch) and match each to an assumption. (Guide: Worked example 2; Practice Q6)
Reasoning
- I can identify which observations support the RNA world hypothesis and which do not. (Guide: “Evidence that fits the hypothesis”; Practice Q2)
- I can evaluate a claim about very old fossils and suggest what further evidence would strengthen it. (Practice Q5)
- I can explain why DNA and proteins could later have replaced RNA in most roles. (Guide: “Why DNA and proteins later took over”; Practice Q7)
- I can explain the limits of laboratory experiments as evidence for events on early Earth. (Guide: Worked example 2; Practice Q6)
All ticked? You have finished Unit 7. Move on to Topic 8.1, Responses to the Environment, or return to the course roadmap.