Cycles of Life & Biomes

What colorless, odorless gas makes up about 8 tenths of the Earth's atmosphere and is essential to life?

• carbon dioxide

• oxygen

• nitrogen

• carbon

Which biome would be BEST suited for a plant that requires warm temperatures and lots of rain?

When animals die & decompose, what is released into the atmosphere?

• methane gas & carbon dioxide

• helium gas

• oxygen

• water

How do nitrogen compounds that are formed in the air reach Earth?

• wind

• drops to Earth by gravity

• birds

• precipitation

This is the most common element in all living things. It is recycled during photosynthesis & cellular respiration.

Nitrogen is cycled through the environment in a similar way that _____ is cycled through the environment.

• water

• wind

• soil

• rock

Animals take in nitrogen they need by eating only plants.

• true

• false

Answer explanation

Animals take in the nitrogen they need by eating plants OR other animals.

What process do decomposers speed up which releases nutrients into the soil?

• photosynthesis

• decaying

• combustion

• respiration

When plants and animals die & decompose, what is released into the air?

Which is NOT an example of a biome?

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