Answer:
What gas does a plant release for animals and humans to use?
oxygen
The oxygen that is produced is released from the same tiny holes through which the carbon dioxide entered. Even the oxygen that is released serves another purpose. Other organisms, such as animals, use oxygen to aid in their survival. The whole process of photosynthesis is a transfer of energy from the Sun to a plant.
What would happen if oxygen was not released from plants?
We would be long gone before the oxygen ran out. Assuming only green plants disappeared, we would still have phytoplankton, microscopic algae and bacteria that live in the oceans and photosynthesise the same way land plants do. They are at the bottom of the food chain, so life in the oceans would continue.
