The Environment and CO2

I've known from my high school biology class days that plants require CO2 to grow and the by-product of that growth is oxygen. Animals, including people, require oxygen to grow and the by-product of that growth is CO2. The planet earth is a closed eco-system. Its evident, at least to me, that our Creator made it that way so that the plants support us and we support the plants. Now is there a balance between the amount of oxygen and CO2? I suppose there is, but what is the limits of the balance? Can we, mortal man, upset that balance? I don't know and I suspect no one else knows. I do know that environmental alarmists like Al Gore have made millions of dollars espousing their belief that man can and is destroying the planet. I suspect God smiles at such folly. Following is an excerpt on this topic from the NASA web page www.NASAexplores.gov:

By definition, a plant is a living thing that produces its own food through photosynthesis. This process uses carbon dioxide and water. Trapping light from the Sun, plants are able to change sunlight’s energy into useable chemical energy. Not only is chemical energy produced, but oxygen is a by-product of photosynthesis. Plants are essential to the balance of life on Earth … and to life, as we know it, on other planets.

Plants may play an important part in NASA’s Vision for Space Exploration. When human beings establish permanent bases on the moon or Mars, they will continue to need food, water, and air, but because those items aren’t widely available on other planets, keeping a ready supply on hand will be a challenge.

After all, Earth is a closed system, even though we can’t see the walls of the system. When human beings consume food, it’s oxidized and carbon dioxide (CO₂) is given off as waste. Plants use the CO₂, along with water and minerals to generate new food and give off more oxygen.