Energy pyramids: how much energy reaches each level

Grade 9 Science Worksheet

Circle the best answer.

1. 1.

   (model data), not to scale. Zee builds a model pyramid. About 10 percent of the energy passes up each step. How much do the secondary consumers hold?

   • 1,000 kJ
   • 10 kJ
   • 100 kJ
   • 1,000,000 kJ
2. 2.

   Energy pyramid (model data), not to scale, 4 steps from the bottom. Unit: kJ. Ari starts a model pyramid with 50,000 kJ at the producers. About 10 percent passes up each step. How much do the tertiary consumers hold?

   • 50 kJ
   • 5,000 kJ
   • 5 kJ
   • 50,000 kJ
3. 3.

   Energy pyramid (model data), not to scale, 3 steps from the bottom. Bo knows the secondary consumers hold 200 kJ. About 10 percent passes up each step. How much do the producers hold?

   • 2,000 kJ
   • 200,000 kJ
   • 20,000 kJ
   • 20 kJ
4. 4.

   Esme asks about the energy that does not pass from the producers to the primary consumers. Which answer is right?

   • 9,000 kJ is destroyed at the first step, so it is gone for good
   • 9,000 kJ goes back to the producers as light to be used again
   • 9,000 kJ is used in life processes or lost as heat
   • 1,000 kJ is lost as heat while 9,000 kJ passes to the next step
5. 5.

   In this model, the energy that does not pass up is used in life processes or lost as heat. Jun wants the total loss across the two steps up to the secondary consumers. How much of the 20,000 kJ is used or lost as heat?

   • 18,000 kJ
   • 19,800 kJ
   • 0 kJ
   • 22,200 kJ

6. Read this first

   Use this

   Energy pyramid (real data, from OpenStax Biology 2e), not to scale, 4 steps from the bottom. Unit: kcal/m²/yr.

8. 6.

   Luz reads real energy data from Silver Springs, Florida. What percent of the producers' energy is the primary consumers' energy?

   • About 83.8 percent
   • About 10 percent
   • About 16.2 percent
   • About 618 percent
9. 7.

   Milo reads the Silver Springs pyramid. What percent of the primary consumers' energy is the secondary consumers' energy?

   Use the picture in question 6.

   • About 88.6 percent
   • About 10 percent
   • About 1.8 percent
   • About 11.4 percent

10. Use the table

    Card (model data). A model ecosystem.

    measure	value
    producers' energy (kJ)	100,000
    share passed up at each step (percent)	10
    least energy a level needs (kJ)	100

11. 8.

    Pia reads a model ecosystem card. How many levels, counting the producers, can this ecosystem support?

    • 5 levels
    • 3 levels
    • 4 levels
    • 2 levels
12. 9.

    Zee reads a different model, in which 20 percent passes up each step. How many levels can it support?

    • 2 levels
    • 4 levels
    • 3 levels
    • 5 levels
13. 10.

    Ari reads a third model ecosystem card. How many levels, counting the producers, can it support?

    • 6 levels
    • 4 levels
    • 3 levels
    • 5 levels