Reading graphs

Before answering, spend 20 seconds identifying:

  1. What is on the x-axis (independent variable)
  2. What is on the y-axis (dependent variable)
  3. The overall trend: increasing, decreasing, plateau, peak, or no pattern
  4. Any anomalies: data points that do not fit the trend

Use this pattern: "As [x-axis variable] increases, [y-axis variable] increases / decreases / stays constant."

Always quote specific data: "The rate increased from 5 units at 10°C to 28 units at 40°C." General statements like "the line goes up" are too vague.

If the trend changes direction, describe both parts: "The rate increased from 10°C to 40°C, then decreased from 40°C to 60°C."

Calculations from data

Common calculations: percentage change = ((final − initial) ÷ initial) × 100. Rate = change in dependent variable ÷ change in time. Always show your working and include units.

Drawing conclusions from data

A conclusion answers the question: "What does the data tell us?" Link the trend to your biological knowledge. "The data shows that enzyme activity increased with temperature up to 40°C because higher temperature increases kinetic energy, leading to more successful enzyme-substrate collisions."