The process by which algae and plants release oxygen is called which?

• A. Respiration
• B. Photosynthesis
• C. Transpiration
• D. Oxidation

Answer: (B)

Photosynthesis is how algae and plants use light to turn water and carbon dioxide into sugars, releasing oxygen in the process. Chloroplasts with chlorophyll capture light energy to drive the reaction that splits water and produces oxygen gas, while fixing carbon dioxide into sugars. This is different from respiration, which uses oxygen to release energy, and from transpiration, which is just water loss, or oxidation, a general chemical reaction. So the release of oxygen by plants and algae comes from photosynthesis.