Step 1: A Euglena starts its day in a sunlit pond. Step 2: It spreads its chloroplasts to capture sunlight. Step 3: It performs photosynthesis to create sugar for energy (Autotrophic mode). Step 4: A cloud covers the sun for several days. Step 5: The Euglena stops photosynthesis and starts swimming toward small bacteria or organic particles. Step 6: It engulfs these particles to get nutrients (Heterotrophic mode), showing how it survives in different environments.