You are an expert secondary school biology teacher and presentation designer. Create a PowerPoint presentation for a beginner-level secondary science class. TOPIC: Properties of Enzymes AUDIENCE: Secondary 1–2 students (ages 12–14), beginner level, no prior biochemistry knowledge DURATION: Around 8 minutes NUMBER OF SLIDES: 10 slides STYLE: Clean, colorful, student-friendly, large readable fonts, one simple visual/diagram per slide, maximum 4 short bullet points per slide LANGUAGE: Simple English. Define key terms briefly. Avoid chemical equations and advanced terms like activation energy or metabolic pathways. CORE MESSAGE: Enzymes are biological catalysts that are specific, reusable, and sensitive to their environment. For each slide, output: - Slide number and title - 3–4 short bullet points - Visual suggestion (diagram, icon, photo, or simple animation) - Speaker notes (about 30–45 seconds of what the teacher should say) Use these analogies: - Enzyme = key / specialized worker - Substrate = lock / specific job - Active site = key shape or worker’s hands - Denaturation = melted key or broken robot Include this simple demo idea: - Raw potato + hydrogen peroxide → bubbles fast (catalase enzyme works) - Cooked potato + hydrogen peroxide → no bubbles (enzyme denatured by heat) SLIDE-BY-SLIDE OUTLINE: Slide 1: Title Slide Title: Enzymes: The Body’s Tiny Workers Subtitle: Properties of Enzymes Visual: Cartoon enzyme “worker” helping a chemical reaction Slide 2: What Are Enzymes? - Biological catalysts - Speed up chemical reactions - Not used up in the reaction - Without them, body reactions would be too slow Visual: Enzyme as a tiny machine speeding up a reaction Slide 3: Why Enzymes Matter - Help digest food - Help build molecules - Keep life processes fast enough - Example: breaking down food in your stomach Visual: Stomach/digestion icon with enzymes working Slide 4: Property 1 – Specificity - Each enzyme has one specific job - Lock-and-key model - Enzyme = key - Substrate = lock - Only the correct key fits Visual: Lock and key diagram with enzyme and substrate Slide 5: Specificity Example - Lactase breaks down lactose (milk sugar) - It does not break down protein - One enzyme, one type of reaction - This is why enzymes are specific Visual: Lactase key fitting lactose lock, but not protein lock Slide 6: Property 2 – Reusable - Enzyme releases products after reaction - Enzyme is not changed or used up - It can work again and again - Like a reusable key or tool Visual: Enzyme doing job, letting go, then moving to next substrate Slide 7: Property 3 – Sensitive to Environment - Enzymes have a delicate shape - Extreme temperature or wrong pH can change shape - Shape is important for the lock-and-key fit - Changed shape = enzyme cannot work Visual: Enzyme shape changing under heat or acid Slide 8: Denaturation - Denaturation means enzyme loses its shape - It can no longer fit its substrate - Caused by high fever, extreme heat, or wrong pH