??? ??? ??? Fossil Fuels Coal, oil, natural gas, and other fuels that are ancient remains of decomposed plants and animals ??? ??? ??? Photosynthesis 6CO??? + 6H???O + light ??? C???H??????O??? + 6O??? ??? ??? ??? Cellular Respiration C???H??????O??? + 6O??? ??? 6CO??? + 6H???O + heat ??? ??? ??? Ocean Acidification the decrease in the pH of the Earth's oceans caused by the uptake of carbon dioxid