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Keep going · science
Photosynthesis
Try it like this
- 1
Set going the balls — use the control to send them round the circuit.
- 2
Follow their path. The balls disappear inside and hit hidden obstacles.
- 3
Listen and pay attention. Hear that click? That was the hidden lever moving.
- 4
Figure out what had to happen for the lever to tip.
A small piece of thinking
What is this, actually?
In front of you is a closed world of balls and one hidden secret. It looks like a ball run, but it is really a model of the most important chemical reaction on our planet.
The run simulates photosynthesis inside a leaf. The balls stand for the raw materials — water and carbon dioxide.
A bigger piece of thinking
What is the lever inside for?
The lever inside is like a chemical balance in a chloroplast. The plant has to collect enough energy from the sun and enough material before it can switch over and make something new.
Once your movement tips the lever, the process is complete. On one side sugar appears — energy for the plant; on the other, oxygen is released for us.
A large piece of thinking
Why is the circuit closed?
The closed circuit is a reminder that nothing in nature is lost — everything keeps going round.
The exhibit shows that photosynthesis is not a static picture in a textbook but a dynamic process that needs a threshold amount of energy and material before the chemical change happens. That is exactly what the hidden lever stands for.
Next time you see it
Ask yourself these when you meet the phenomenon in the real world.
Where does a plant get its water, and where its carbon dioxide?
What happens inside a leaf in the dark?
How much oxygen does one tree make?
This is how scientists think.
More curiosity questions
- Why are leaves green?
- Would photosynthesis work under blue light?
- What would happen if plants stopped photosynthesising?
