Broad and flat
Large surface area catches more light.
P5 SCIENCE · PSLE READY
How does a leaf
make food?
Plants are not just sitting in the sun. Inside every green leaf, a tiny food factory is working.
Start exploring ↓☼
LIGHT
CO₂
H₂O
THE OUTPUTFOOD + OXYGEN
01 / THE BIG IDEA
Photosynthesis is a
food-making process.
Green plants use light energy to make food. The process happens mainly in their leaves.
CARBON DIOXIDEfrom air
+WATERfrom roots
→FOODstored as starch
+OXYGENreleased to air
☼ LIGHT ENERGY● CHLOROPHYLLare needed for the reaction.
02 / WHAT A LEAF NEEDS
Four clues.
One process.
Tap each clue to see the job it does in the leaf factory.
Light provides the energy.
The Sun is the original source of energy for photosynthesis. A plant kept in darkness cannot make food.
03 / LEAF DESIGN
Built like a
solar panel.
Leaves have features that help them make food efficiently.
Thin
Gases can move in and out quickly.
Many chloroplasts
Chlorophyll absorbs light energy.
Stomata
Tiny openings allow carbon dioxide in and oxygen out.
04 / THE INVESTIGATION
Can a leaf prove
it made food?
Run the classic starch test. Change one condition and predict what will happen.
CHOOSE THE LEAF CONDITION
RESULTChoose a condition, then run the test.
Remember: iodine solution turns blue-black when starch is present. Starch is evidence that the leaf made food.
05 / CHECK YOUR THINKING
Ready for
the PSLE twist?
Answer each question. Read the explanation after you submit.
QUESTION 1 OF 50 correct
THE ONE-MINUTE RECAP
Light + water + carbon dioxide
→ food + oxygen
Chlorophyll captures the light energy. Food is made and stored as starch. Oxygen is released.
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