How do plants contribute to oxygen production in ecosystems?

Plants make oxygen during photosynthesis. They use sunlight, water, and carbon dioxide to produce >glucose (energy)< Oxygenstomata.

How the process works

Light-dependent reactions

• Chlorophyll absorbs sunlight.
• Water ((H_2O)) splits, releasing oxygen ((O_2)) and hydrogen.

Oxygen release

• The (O_2) formed from water splitting is not needed later, so it’s released to the atmosphere.

Carbon fixation

• The remaining hydrogen helps build glucose.
• Oxygen leaves the leaf via stomata.

Light-independent reactions (Calvin cycle)

• Plants take in carbon dioxide ((CO_2)).
• Using the captured energy, they form glucose, their food.

Where does it happen?

Terrestrial plants

• Trees, grasses, and other land plants produce large amounts of oxygen.
• Forests are often called the “lungs of the Earth.”

Aquatic plants

• Phytoplankton and other aquatic plants in oceans and lakes are major oxygen producers, contributing over half of Earth’s atmospheric oxygen.