Photosynthesis
Photosynthesis is the process plants use to make their own food, converting light energy into chemical energy stored in glucose.
The word equation
Carbon dioxide + water → glucose + oxygen (using light energy, captured by chlorophyll in the leaves).
Limiting factors
Photosynthesis can be slowed down by too little light, too little carbon dioxide, or too low a temperature — whichever of these is in shortest supply limits the overall rate.
Practice
If a plant is given plenty of light and CO₂ but kept in the cold, why might it still photosynthesise slowly?