1. Energy Cycle of Biosphere
Solar energy has been fixed in one form or another on the earth throughout much of earth's 4.5 billion years history. ... Marine plant cells accumulated for hundreds of millions of years, gradually building an atmosphere that screened out the most destructive of the sun's rays and opened the land to exploitation by living systems. ... Only about a tenth of 1 percent of the energy received from the sun by the earth is fixed in photosynthesis. ...
- Word Count: 711
- Approx Pages: 3
- Grade Level: Undergraduate