IB Bio 4.2 + C.2 Reading Quiz

At each trophic level, energy is lost through respiration, heat, etc. How is new energy introduced into the ecosystem?

• Heat

• Nutrients

• Photosynthesis

• Recycling

In ecosystems the amount of energy that passes from one trophic level to the next is called the conversion

efficiency. What is the average conversion efficiency from primary to secondary consumers in most ecosystems?

• 1%

• 10%

• 33%

• 50%

The diagram shows a pyramid of energy for a wetland environment. What units would be appropriate for the

values shown?

• kg*yr^-1

• kg*(m^-2)*yr^-1

• J*m^-2

• mg dry mass *m^-3

Why do food chains in an ecosystem rarely contain more than five organisms?

• Nutrients are recycled by the decomposers back to the producers.

• Nutrients are lost from the ecosystem when organisms die.

• The conversion of food into growth by an organism is not very efficient.

• Energy is recycled by the decomposers back to the producers.

What IS NOT a valid explanations to why the levels of a pyramid of energy differ in size?

• There is massive energy loss between trophic levels

• Energy is used/released through cell respiration, heat, metabolism, or movement

• Not everything of an animal is eaten by predators (hairs, cellulose)

• There are usually more detritivores than producers in the ecosystem

Approximately how much biomass is represented by parasites in this ecosystem. [Each mark is 20kg]

• 10 kg

• 20 kg

• 100 kg

• 200 kg

What does NOT occur to species diversity during primary succession

• Eukaryotic animals that can survive on purely abiotic factors take over the landscape

• More organic material slowly accumulates as the soil develops

• Increasing species diversity as more resources are available

• Few colonizing species establish themselves in harsh conditions

How is energy passed from one trophic level to the next?

I. Food

II. Light

III. Heat

• A. I only

• B. I and II only

• C. II and III only

• D. I, II and III