Year 9 Science · Unit 1 · Lesson 13
Challenge Worksheet
Learning Goals
Evaluate the claim
Someone claims...
"A social media influencer claims: 'If you just eat organic food and exercise, you will never get cancer.' She cites a statistic that eating well reduces cancer risk by 33%."
(a) What part of this claim is supported by the science in this lesson? Refer to specific lesson content in your answer.
(b) What is scientifically incomplete or misleading about this claim? Consider the role of genetic factors, environmental exposures, and the meaning of "reduces risk" versus "eliminates risk".
(c) The influencer does not cite where the "33%" figure comes from. Using what you know about case fatality rates and incidence rates, explain why the context of any statistic matters. What questions would you ask before accepting this number?
1. A researcher wants to investigate whether daily exercise reduces the incidence rate of cardiovascular disease in Australian adults. Write a strong scientific hypothesis for this question using if–then–because format. Then identify the independent variable, the dependent variable, and two controlled variables for the investigation.
2. Australia has three national screening programs for non-infectious diseases: BreastScreen, the National Cervical Screening Program, and the National Bowel Cancer Screening Program. Explain why these programs focus on people in specific age groups rather than the entire population. Use the concept of case fatality rate and early detection in your answer.
Wrap Up
In one sentence, what was the main idea of this lesson?