Food web

Exam 4 review sheet Chapter 3 Hydro cycle Solar energy heats Earth, and causes evaporation Evaporated water condenses into clouds Water returns to Earth as precipitation Precipitation falling on land is taken up by plants, runs off along the land surface, or percolates into the soil and enters the groundwater Carbon cycle Carbon is the most important element in living organisms makes up 20 percent of total body weight. Produces convert CO2 into sugars Sugars are converted back into CO2 Some carbon can be buried Human extraction of fossil fuels brings carbon to Earth?s surface, where it can be combusted C02 in the atmosphere and CO2 dissolved in water are constantly exchanged Combustion converts fossil fuels and plant material into CO2 Nitrogen cycle