Cycles of Matter — Unit test Answers

Scott made a model of the water cycle by filling a tub with water, covering the tub with clear plastic, and placing a heat lamp over the tub. After a few days, he observed water droplets collecting on the plastic wrap.What process formed the water droplets in Scott’s model?

Which best describes a role of animals in the water cycle?

Which human activity would most likely decrease the amount of carbon in the atmosphere?

How is the nitrogen cycle important to humans?

Which process occurs when bacteria converts nitrogen gas to a usable form?

Which best compares the roles of nitrogen-fixing bacteria and certain decomposers in the nitrogen cycle?

The diagram illustrates part of the carbon cycle.

water vaporgroundwaterrunoffcondensation

Cleo has a vegetable garden and wants to increase the amount of nitrogen in the soil.How can she most likely do this?

Kate wrote the steps of the carbon cycle to describe how carbon is cycled through specific organisms. The steps are in random order.1 - The rabbit decomposes.2 - The rabbit eats the carrot plant. 3 - The carrot plant takes in carbon dioxide from the air during photosynthesis.4 - Carbon compounds are returned to the soil.