Question

How would earths atmosphere be different if organisms capable of photosynthesis has not evolved?

Answer 1

In a world where photosynthetic plants have not evolved, everything would be extremely different. The world is based on green plants which provide food for almost all living organisms, provide us with products like medicine and materials, and they form fossil fuels, which are used by just about everyone around the world. The world would be much less colorful and diverse, and there would not be any animals as these plants are food for a lot of animal species we have now. We humans might have not even lasted very long without green plants. Not only are they food sources, but they help circulate oxygen and carbon dioxide in the environment.

Answer 2

The Earth's atmosphere would have little or no oxygen. A by-product of photosynthesis is oxygen. Photosynthesis is the process by which green plants use energy from the sun to make their own food in the leaves. The process uses sun light, water and carbon dioxide to yield oxygen and simple sugars. The simple sugars are stored in form of starch for future use by the plants, while oxygen is either used for cellular respiration or released to the atmosphere. The process of photosynthesis adds oxygen to the atmosphere and uses carbon dioxide from the atmosphere.