Ecosystem Cycles

Plants and animals cannot use nitrogen directly from the air.

• True
• False

What converts nitrogen into a useable form for plants and animals?

• bacteria
• fungi
• rain

Plants and animals need nitrogen to make __________.

• Protein
• Carbohydrates
• Lipids
• Minerals

In the energy pyramid here, which organisms have the most energy available?

• Producers
• Carnivores
• Herbivores
• Top Predator

In the energy pyramid below, which organism has the least amount of energy available?

• Producers
• Herbivores
• Carnivores
• Top Predator

All food webs and food chains begin with _________________.

• primary consumer
• producers
• secondary consumers
• predators

What is photosynthesis?

• The process in which humans eat their food
• When a photographer takes a photo.
• To get your pictures from the photo lab.
• The process in which plants make their food.

In the carbon cycle, producers take in the gas __

• carbon dioxide
• oxygen
• nitrogen
• carbon monoxide

Nitrogen gas accounts for what percentage of the atmosphere?

• 1%
• 7%
• 55%
• 78%

How is Nitrogen removed from the air and put into compound that living things can use?

• plants
• photosynthesis
• chemosynthesis
• nitrogen fixing bacteria