Chapter 5 Test: How Ecosystems Work

Which of the following statements is NOT correct?

• Plants and other producers get their energy directly from the sun.
• Animals get their energy from the sun indirectly.
• Bacteria that live deep in the ocean get their energy from hydrogen sulfide in hot water.
• Consumers get their energy directly from the sun.

Which kind of organism obtains energy only from producers?

• decomposers
• herbivores
• omnivores
• carnivores

If an insect eats a plant and a bird eats the insect, about how much energy from the plant is stored in the insect for the bird to use?

• 90%
• 50%
• 10%
• 1%

Which gas makes up 78% of our atmosphere but can be used by plants only when transformed by bacteria first?

• nitrogen
• oxygen
• hydrogen
• carbon dioxide

Which of the following plants is likely to be a pioneer species?

• lichen
• grass
• shrub
• oak tree

What kind of natural disaster helps some forest communities by allowing some trees to release their seeds, clearing away deadwood, and encouraging new growth?

• fire
• flood
• windstorm
• drought

Where would an ecologist be LEAST likely to go to study primary succession?

• a new island formed by a volcanic eruption
• a gravel-filled valley that had been covered by a glacier until recently
• a locked, abandoned asphalt parking lot in New York City
• the Amazon Rain Forest

Which statement describes how humans are affecting the balance of carbon dioxide released into the atmosphere?

• Fewer agricultural crops are planted, reducing the amount of carbon dioxide released into the atmosphere
• burning fossil fuels in great quantities has increased the amount of carbon dioxide in the atmosphere
• overgrazing of grasslands has reduced the amount of carbon dioxide in the atmosphere.
• Severe drought in large areas of the world has decreased the amount of carbon dioxide that is released into the atmosphere.

Which of the following is NOT a true statement about cellular respiration?

• it is essentially photosynthesis in reverse
• oxygen is one of the primary reactants
• it produces energy for organisms to use
• sugar molecules are its primary products

Plants play a crucial role in the carbon cycle because they

• do not release carbon dioxide during cellular respiration
• allow carbon to enter an ecosystem through photosynthesis
• have special bacteria that live in their root system
• are chemically converted into fossil fuels when burned