Because it's the most abundant gas in atmosphere , required by plants
Answer:
The cell membrane controls what goes in and out by having protein channels that act like funnels in some cases and pumps in other cases. Passive transport does not require energy molecules and happens when a funnel opens in the membrane, letting molecules flow through.
Diffraction could have caused it. This is where a wave encounters an obstacle or a slit. It happens when there is bending of light around the corners of an obstacle. It is often described as the interference of waves according to the Huygens–Fresnel principle.
In the process of photosynthesis, phytoplankton release oxygen into the water. Half of the world's oxygen is produced via phytoplankton photosynthesis. The other half is produced via photosynthesis on land by trees, shrubs, grasses, and other plants.