Video narration
How can something too small to see keep itself alive? Think of a one-room kitchen: its walls hold the work inside, while instructions and tools help things get done. A cell is similar-not literally a kitchen, but a tiny place where parts work together. Take a bacterium, one kind of single-celled microbe. A bacterial cell isn't just a tiny blob. It's a working system. Its membrane separates inside from outside, and its cytoplasm is the space where work happens. DNA holds instructions; ribosomes build proteins from messages based on them. Like a kitchen, these parts depend on one another: the boundary holds the system together, while instructions and proteins support its work. So how does a tiny cell stay alive? It stays alive by keeping its instructions and working parts together inside one boundary, like a one-room kitchen that keeps running.