Year 7 Science · Unit 1 · Lesson 11
Challenge Worksheet
Learning Goals
Evaluate the claim
A student concludes…
"Our duckweed experiment proves that light is the only factor controlling plant growth. The duckweed in the dark container died after 7 days, which shows that without sunlight, no life can survive on Earth. Therefore, if you want any plant to grow fast, just give it more light."
(a) What part of this conclusion is correct and supported by the investigation results?
(b) Identify two logical errors or overstatements in the conclusion. Explain why each one is a problem.
(c) What additional evidence or further investigations would improve this conclusion?
1. Explain how a fault affecting chloroplasts in a plant's leaf cells could affect the whole plant. In your answer, connect at least three levels of organisation: cell → tissue → organ (leaf) → whole organism. Use specific examples.
2. A new fungal disease is destroying liver cells in koalas. Using your knowledge of specialised cells, tissues, organs and organ systems, predict and explain how damage that starts in individual liver cells could affect the whole koala. Refer to at least three levels of organisation.
Wrap Up
What was the most surprising or interesting idea you encountered in Unit 1?