Explanations:Plants are essential for the production of oxygen in the Earth's atmosphere. This process is primarily carried out through photosynthesis, a biochemical process in which plants use sunlight, water, and carbon dioxide to produce glucose and oxygen. The oxygen produced during photosynthesis is released into the atmosphere, which is crucial for the survival of most living organisms, including humans and animals, which rely on oxygen for respiration.
Photosynthesis can be represented by the following chemical equation:
6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂
Here, carbon dioxide (CO₂) and water (H₂O) are converted into glucose (C₆H₁₂O₆) and oxygen (O₂) with the help of light energy. The oxygen produced is a byproduct of this process and is released into the atmosphere.
If all plants were to vanish from the Earth, the production of oxygen through photosynthesis would cease. This would lead to a significant decrease in the levels of atmospheric oxygen. While other sources of oxygen exist, such as the breakdown of certain minerals and the release of oxygen from the ocean, these sources are not sufficient to maintain the current levels of atmospheric oxygen necessary for the survival of most life forms.
It is important to note that the absence of plants would not eliminate other gases in the atmosphere. For example, carbon dioxide would still be present due to the respiration of animals and human activities such as burning fossil fuels. Similarly, nitrogen, which makes up about 78% of the Earth's atmosphere, would remain unaffected by the absence of plants.
Therefore, the correct answer is that if all plants were to vanish from the Earth, there would be no oxygen produced through photosynthesis, leading to a significant reduction in atmospheric oxygen levels.