Cycles Through The Ecosystem

Nitrogen Cycle

Our atmosphere is _____ nitrogen gas

• 50%

• 78%

• 68%

• 40%

Nitrogen Cycle

Animals and plants _______ use all of the nitrogen found in our _______

• cannot directly;

  atmosphere

• can;

  atmosphere

• cannot directly;

  solar system

• None of these

Nitrogen Cycle

TRUE OR FALSE

Only special bacteria can directly use Nitrogen and "fix it" so other organisms can benefit.

• TRUE

• FALSE

Nitrogen Cycle

What are the special bacteria that can directly use Nitrogen and "fix it" so other organisms can benefit called?

• Denitrificating

• Nitrogen-Fixing

• Nitrogen-Antibodies

• Nitrates

Nitrogen Cycle

Higher organisms use nitrogen to make _______

• energy

• food

• waste

• protein

Nitrogen Cycle

Animal waste decay by the action of bacteria which create _____ and ______ products rich in nitrogen, and useful for plants to use again

• Phosphorous: nitrate

• nitrogen; oxygen

• ammonia; nitrate

• Calcium and Phosphate

Nitrogen Cycle

_________ bacteria in the soil, can break down ammonia into the gaseous form of nitrogen, which is not available for use by plants and animals.

• None of these

• nitrate

• nitrogen-fixing

• denitrificating

Nitrogen Cycle

In another part of the cycle, animals eat _______ which is returned to the soil by animal ______ or decaying ________ or _______

• plants; phosphates; animals; waste

• plants; waste; animals; plants

• animals; proteins; nitrates; calcium

• nitrates; waste; ammino acids; Phosphates

THE NITROGEN CYCLE

What is happening at #1 and #6? (Check all that apply)

• Atmospheric Nitrogen

• ammonia

• soil nitrates

• Nitrates

• decomposers

Nitrogen Cycle

What is happening at #2?

• Nitrates

• Decomposers

• Animal Waste

• Plant Protein