High School Enzyme Activity Lab Lesson Plan

Learning Objectives

• Formulate a hypothesis about temperature and enzyme activity.
• Collect and graph quantitative data on reaction rates.
• Explain results using knowledge of protein structure and denaturation.

• Drop a small piece of liver into hydrogen peroxide at room temperature. Observe bubbling.
• Ask: 'What's happening? What gas is being produced?'
• Connect: 'Catalase is an enzyme in liver that breaks down H₂O₂. Today we test how temperature changes its activity.'

• Students write a hypothesis: 'If we increase temperature, then enzyme activity will ___ because ___.'
• Review lab setup: 4 temperature conditions (0°C, 25°C, 37°C, 60°C).
• Safety review: goggles, gloves, handle hot water with tongs.

• Groups run the enzyme reaction at each temperature and measure bubble height after 30 seconds.
• Record in data table. Repeat each condition twice for reliability.
• Teacher circulates for safety and data accuracy.

• Groups create a bar graph of average bubble height vs. temperature.
• Class discussion: 'At which temperature was activity highest? What happened at 60°C?'
• Connect to denaturation: high temperatures change protein shape, reducing enzyme function.

• Students write a CER conclusion. Claim answers the research question. Evidence cites specific data. Reasoning connects to protein structure.
• Peer review in pairs: check for data citations and mechanistic reasoning.
• Lab cleanup. Collect notebooks.

Assessment

• Student product: Hypothesis, data table, graph, and CER conclusion.
• Criteria: Clear hypothesis, accurate data, graph with labels, CER with data and mechanistic reasoning.
• Success indicator: 80% of students explain denaturation as the reason for decreased activity at high temperatures.