Photosynthesis
How a plant turns passing sunlight into lasting structure. Explore six stages, then experiment with the inputs that support the process. Start with the big picture, then look inside a chloroplast. No calculations are needed. The interactive guide also works offline.
Use Next stage, select a stage, or use the arrow keys on the stage tabs. These are six views of cooperating processes, not six isolated events that take turns. Motion is a schematic, not a measurement.
Why it matters:
How the two systems cooperate
In the thylakoid membranes, light and water drive electron transfer, producing oxygen, ATP, and NADPH.
In the stroma, ATP and NADPH support fixation of CO₂ into three-carbon sugar precursors.
Overall simplified equation: 6 CO₂ + 6 H₂O + light → C₆H₁₂O₆ + 6 O₂.
This is a net summary, not a literal single reaction. The oxygen released during photosynthesis comes from water.
Explore the limiting inputs
Select low, medium, or high availability. The demonstration uses a simplified “weakest input” model: the least available input limits the indicated rate. The categories are relative settings, not measured concentrations or a prediction for a real plant. Actual photosynthesis also depends on temperature, species, leaf condition, and many other factors. More light or water is not always better: excessive light can damage leaves, and waterlogging can harm roots.
A thought to keep: Photosynthesis converts brief arrivals of energy into durable chemical bonds. A leaf is not just a solar collector; it is a coordinated system of membranes, molecular machines, gradients, and feedback.
Self-contained HTML • no external scripts, fonts, images, or network requests. The animation and controls use no external resources. Reading links open external educational sources only when selected.
All six views
Keep exploring
New to plant growth? Read The Little Seed’s Big Beginning with Leo, Pip, and Gidget.
A few words to unlock the guide: A chloroplast is a photosynthesis compartment in a plant cell. Thylakoids are membranes inside it; the stroma is the surrounding fluid. ATP transfers usable chemical energy, and NADPH carries electrons. G3P is a three-carbon molecule used to build carbohydrates. The Calvin cycle depends on products of the light reactions; “light-independent” does not mean it works only at night.
For deeper reading: OpenStax: photosynthesis overview and the Calvin cycle.