Each learning path is one chapter: a guided route through a topic, one small course at a time. Pick a class to see its chapters in order.
A plant stands still in the sun, and a dog runs after a ball. Both are alive because their cells keep working, day and night. In this chapter you see how living things get their food, how they release energy from it, how they carry materials around the body, and how they remove their wastes. You follow a bite of food through your own body, count breaths and heartbeats, and use Python with real numbers about the body.