Cycles of Matter

Biogeochemical cycles include both the biotic factors and abiotic factors.

• True

• False

During the water cycle, water from underground reservoirs can seep into _________.

• oceans

• rivers

• springs

• all of these

Most of the earth's carbon is trapped in __________.

• ocean

• underground

• both ocean and underground

Nitrogen can be fixed by

• bacteria in the roots of legumes.

• bacteria in the soil.

• lightning strikes.

• all of these.

Humans get their nitrogen from

• eating plants and plant-eating animals.

• the nitrogen in the atmosphere.

• the bacteria in the intestines.

Nitrogen-fixation is the _______ of inorganic nitrogen to organic nitrogen.

Most free oxygen is produced by decay of minerals in the earth's crust.

• True

• False

The biosphere has the ability to maintain balance which is known as _______.

The idea that small changes can cause drastic effects is known as ______.

• cause and effect theory

• consequences

• butterfly effect

_____________ trace the flow of matter in the biosphere and geosphere in a chemical level.