When trees grow, where does the matter come from?

We all know that trees breathe in carbon dioxide, but what happens next?


Asked by: Toby Graham, Shrewsbury

Trees get their matter from the carbon dioxide in the air, and the water they take in through their roots, with just a small amount of nutrients coming from the soil itself. During photosynthesis, trees use the Sun’s energy to break apart the carbon dioxide (CO2) and water (H2O) molecules to form glucose (C6H12O6) and oxygen (O2). Some of this glucose is used to respire, while the rest goes into forming cellulose, the primary building block for new branches, stems, leaves and roots.

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