80 marks of written answers, many built on a scenario, data or an experiment.
Marks
80 of the examination's 120
Questions
Short-answer and extended-answer, many with parts; the number varies each year
Material
May refer to visual or written material, scenarios and experiments
Answers
Written in the Question and Answer Book
What it asks for
Variables, controls and hypotheses for an experiment.
Reading data: rates, means and percentage change, and what they show.
Explanations that link two ideas, with the command word and marks as a guide to length.
Try 2 questions
Question 1
Rate of photosynthesis at five light intensities and two carbon dioxide concentrations.
Light intensity / arbitrary units
Rate at 0.04% carbon dioxide / arbitrary units
Rate at 0.10% carbon dioxide / arbitrary units
0
0
0
100
10
10
200
18
24
300
20
32
400
20
33
The table shows a hypothetical plant's rate of photosynthesis at five light intensities and two carbon dioxide concentrations, at 25 °C. For the plant at 0.04% carbon dioxide, which factor limits the rate at 100 units of light and at 400 units of light, and by what percentage does raising the carbon dioxide to 0.10% increase the rate at 400 units?
Question 2
A student places a pondweed shoot in water at 25 °C and counts the oxygen bubbles it releases in one minute, with a lamp placed 10, 20, 30 and 40 cm from the beaker. What is the dependent variable?