Why is fertile soil a valuable resource? 1. Humus is present in it
2. It is quickly being renewed
3. There is a large amount of it
4. There is a limited amount of it

Which phrase is the best summary of the model shown? a. the transfer of the sun's energy through trophic levels b. a series of aerobic and anaerobic reactions c. a transformation of light energy into chemical energy d. the breakdown of food molecules

Wich organism obtains its energy from dead or decaying matter

Which of the following is the most likely outcome of global warming