Unlocking Enzymes: Keys to Life

Unlocking Enzymes: Keys to Life

Year 10 Biology Understanding Enzyme Activity Lock and Key Model

WALT (We Are Learning To)

Describe enzyme activity using the lock and key model Explain factors affecting enzyme activity Apply knowledge to real-world scenarios Understand enzyme specificity and catalysis

Do Now: Retrieval Practice

1. What is a catalyst? 2. Name three types of biological molecules 3. Where are proteins made in cells? 4. What happens to reaction rate with heat? 5. Define 'active site'

The Hook: What Makes This Possible?

What Are Enzymes?

Biological catalysts made of proteins Speed up chemical reactions in living organisms Remain unchanged after the reaction Essential for life processes

The Lock and Key Model

Enzyme = Lock Substrate = Key Active site = Keyhole Only specific substrates fit specific enzymes

Lock and Key Model Steps

{"left":"1. Substrate approaches enzyme\n2. Substrate binds to active site\n3. Enzyme-substrate complex forms","right":"4. Reaction occurs rapidly\n5. Products are released\n6. Enzyme returns to original state"}

Guided Practice: Enzyme Modeling

Work in pairs Use puzzle pieces to model enzyme-substrate interaction Demonstrate lock and key mechanism Identify: enzyme, substrate, active site, product

Factors Affecting Enzyme Activity

Temperature pH (acidity/alkalinity) Enzyme concentration Substrate concentration

Temperature Effects on Enzymes

Low temperature = slow molecular movement Optimal temperature = maximum activity High temperature = enzyme denaturation Denatured enzymes lose their shape permanently

pH Effects on Enzymes

Each enzyme has an optimal pH range Extreme pH changes enzyme shape Pepsin works in acidic stomach (pH 2) Trypsin works in alkaline small intestine (pH 8)

Investigation: Enzyme Concentration

Observe enzyme reaction rates Vary enzyme concentration Record time for color change Plot results on graph Discuss relationship between concentration and rate