As energy moves from one trophic level to another, about ______ is lost as heat. 

Which is a component of cell theory? 

 A(n) _____ is a possible explanation for what is observed that is based on some previous knowledge, can be tested, and shown to be false. 

Water is very cool and it has many interesting properties. Which of the following is NOT a property of water?

The pH scale is a range from 

If you discovered a new species of bottom dwelling rockfish in a fisherman’s net, you could assume it was from the 

The second law of thermodynamics is that 

The nitrogen cycle is disrupted by humans in two primary ways, burning fossil fuels releasing nitrogen oxides and 

The first law of thermodynamics is that

“Chemical X” was used widely in the United States as an insecticide for many years. Eventually, research showed “chemical X” was a persistent chemical that bioaccumulated and biomagnified in the environment. The chemical was later banned from use in the United States.   You are writing a report on the history of chemical X in the United States. Your instructor says that all sources used for your report must be primary sources. Which of the following would you choose?