Calculate energy transfer efficiency between trophic levels

Question 1

Producers in a field store 20000 kJ/m² of energy per year. Primary consumers gain 2000 kJ/m². What is the efficiency of energy transfer, in %?

Answer %

Question 2

Why is energy transfer between trophic levels inefficient?

• A. Predators eat too much
• B. Much is used in respiration and lost as heat, and some material is not eaten or digested
• C. Consumers photosynthesise
• D. Energy is destroyed at each level

Question 3

Producers capture 1000000 kJ. 20 % is passed to primary consumers and 10 % of that is passed to secondary consumers. How much energy reaches the secondary consumers, in kJ?

Answer kJ

Question 4

Producers in a field store 20000 kJ/m² of energy per year. Primary consumers gain 4000 kJ/m². What is the efficiency of energy transfer, in %?

Answer %

Question 5

Pyramids of biomass are usually pyramid-shaped. Why?

• A. Producers are always heavier individually
• B. Predators are always smaller than prey
• C. It is just how they are drawn
• D. Less biomass can be supported at each higher level because energy is lost

Question 6

Producers capture 200000 kJ. 10 % is passed to primary consumers and 10 % of that is passed to secondary consumers. How much energy reaches the secondary consumers, in kJ?

Answer kJ

Question 7

Producers in a field store 25000 kJ/m² of energy per year. Primary consumers gain 3000 kJ/m². What is the efficiency of energy transfer, in %?

Answer %

Question 8

Why are food chains rarely longer than 4 or 5 levels?

• A. Plants stop growing
• B. Animals refuse to eat higher animals
• C. Too little energy is left to support another level
• D. There are not enough species on Earth

Question 9

Producers capture 200000 kJ. 10 % is passed to primary consumers and 10 % of that is passed to secondary consumers. How much energy reaches the secondary consumers, in kJ?

Answer kJ

Question 10

Producers in a field store 20000 kJ/m² of energy per year. Primary consumers gain 4000 kJ/m². What is the efficiency of energy transfer, in %?

Answer %

Question 11

Pyramids of biomass are usually pyramid-shaped. Why?

• A. Producers are always heavier individually
• B. Predators are always smaller than prey
• C. Less biomass can be supported at each higher level because energy is lost
• D. It is just how they are drawn

Question 12

Producers capture 100000 kJ. 10 % is passed to primary consumers and 10 % of that is passed to secondary consumers. How much energy reaches the secondary consumers, in kJ?

Answer kJ

Question 13

Producers in a field store 20000 kJ/m² of energy per year. Primary consumers gain 2400 kJ/m². What is the efficiency of energy transfer, in %?

Answer %

Question 14

Why is eating plant foods often more energy-efficient for feeding people than eating meat?

• A. Fewer trophic levels means less energy is lost before it reaches people
• B. Meat contains no protein
• C. Animals photosynthesise
• D. Plants contain no energy

Question 15

Producers capture 1000000 kJ. 20 % is passed to primary consumers and 5 % of that is passed to secondary consumers. How much energy reaches the secondary consumers, in kJ?

Answer kJ

Question 16

Producers in a field store 20000 kJ/m² of energy per year. Primary consumers gain 4000 kJ/m². What is the efficiency of energy transfer, in %?

Answer %