Yeast Feast SlidesYeast Feast The Invisible Science of Breathing Cells Life Science Unit Grade 7 Warm Up Quick Write: Answer these two questions in your notebook. 1 Where does the air come from when you blow up a balloon? 2 Where does the air come from in the experiment we are about to watch? The Case of the Inflating Balloon Watch closely. We are looking for Reactants (what goes in) and Products (what comes out). Embedded media Scientific Pause: 0:18 Copy the chemical equation into your notes exactly as shown! The Chemical Recipe Glucose + Oxygen → Heat + CO2 + Water Reactants What the cell uses to get energy. Products What the cell makes as waste. What is "Glucose"? In biology, "Glucose" is just a fancy scientific name for Sugar. "It is the fuel that powers every living cell, from the yeast in your bread to the muscles in your legs!" C₆H₁₂O₆ Molecule Mapping The Mission Draw Bottle B from the experiment. Inside the bottle, draw the Yeast Cells. Write the Chemical Equation. Use arrows to show movement! Arrow Checklist IN: Glucose & Oxygen OUT: CO2 (into balloon) Big Picture "Is the yeast in the bottle alive? How do you know for sure based on what we saw?" Evidence? Metabolism? Gases?
Cellular Respiration Anchor ChartCellular Respiration Converting Fuel into Energy The Big Idea Cellular Respiration is the process that cells use to break down glucose (sugar) to create usable energy. Without this process, life as we know it would not have the power to grow, move, or survive! The Chemical Recipe Glucose Sugar Oxygen Gas Metabolism Heat/Energy CO2 Gas Waste Water Reactants What goes in! Products What comes out! The Lab Model Bottle A Control Group (No Sugar) Bottle B Experimental Variable (+ Glucose) Vital Vocabulary Glucose: Simple sugar fuel. Metabolism: Chemical reactions in a living cell. CO2: Carbon Dioxide gas waste. Conclusion The balloon on Bottle B inflated because the yeast cells ate the glucose and released Carbon Dioxide gas through Cellular Respiration! Did you know? Humans do this too! We breathe out the CO2 our cells make.
Yeast Feast Reflection JournalYeast Feast Journal Unit: Life Processes | Lesson: Cellular Respiration Scientist: Date: 1 Molecule Mapping: Bottle B Draw Bottle B from the experiment. Your diagram must include: • The yeast cells inside the water. • The chemical equation written inside the bottle. • Blue Arrows showing Glucose and Oxygen going In to the cells. • Orange Arrows showing CO2 coming Out of the cells and into the balloon. Reactants (Inputs) What the yeast "ate" Products (Outputs) What the yeast produced 2 Scientific Reflection 1. Is the yeast in Bottle B alive? What specific evidence from the experiment proves your answer? 2. Why did the balloon on Bottle A stay flat? Explain using the concept of "reactants." 3. How is the process happening in the yeast bottle similar to what happens in your own body right now? Data recorded during the Cellular Respiration Investigation
Yeast Feast Teacher GuideTeacher Guide: Yeast Feast Grade 7 Biology | Topic: Cellular Respiration Duration: 45-50 min Learning Objective Students will explain the chemical process of cellular respiration, identifying glucose and oxygen as reactants and carbon dioxide, water, and energy as products. Materials Needed Yeast Feast Slides & Anchor Chart Yeast Feast Reflection Journal (1 per student) Video link: https://www.youtube.com/watch?v=j\_3M70E9ciA Instructional Sequence 5 min Warm-up: Quick Write Use Slide 2. Prompt students to consider the source of gas in their own lungs vs. the source of gas in the experiment. This seeds the idea of biological production of gases. 10 min Video Viewing & Equation Analysis Play video (Slide 4). MUST PAUSE at 0:18 for students to copy the equation. Discussion points: Glucose: Clarify that this is the scientific term for the sugar added to Bottle B. Reactants vs. Products: Use the Anchor Chart to explain that reactants are "inputs" and products are "outputs/waste." 20 min Molecule Mapping Activity Hand out the Reflection Journal. Students model the movement of molecules. Circulate to ensure arrows show Glucose/Oxygen going into the yeast cells and CO2 coming out into the balloon space. 10 min Reflection & Debrief Discussion: "Is the yeast alive?" Key takeaway: Yes, because it shows metabolism (consuming food) and gas exchange (producing waste), both indicators of life. Answer Key: Reflection Journal 1. Is the yeast alive? Evidence? Yes. Evidence: The production of CO2 gas (inflated balloon) and the foam in the bottle indicate that a chemical reaction (metabolism) is occurring inside the cells. 2. Why did Bottle A stay flat? (Reactants) Bottle A was missing a key reactant: Glucose (sugar). Without the fuel, the yeast could not perform cellular respiration and produce CO2 gas. 3. Connection to the human body? Just like the yeast, our cells take in glucose (from food) and oxygen (from breathing) to make energy. We also breathe out CO2 as a waste product, just like the yeast filling the balloon.
