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?

   • 10 kJ
   • 100 kJ
   • 1,000 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?

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

   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 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
   • 9,000 kJ goes back to the producers as light to be used again
4. 4.

   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?

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

5. Read this first

   Use this

   not to scale. In this model, the energy that does not pass up is used in life processes or lost as heat.

6. 5.

   The primary consumers hold 1,000 kJ and pass 100 kJ up. Kira's friend says the other 900 kJ is gone. Which reply is best?

   • It was destroyed, which is why the next step is smaller
   • It passed up as well, so the next step really holds 1,000 kJ
   • It went back to the producers, who use it again
   • It was used for life processes or left as heat, so it was not destroyed

7. Use this

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

9. 6.

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

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

    Noah reads the Silver Springs pyramid. What percent of the secondary consumers' energy is the tertiary consumers' energy?

    Use the picture in question 6.

    • About 0.1 percent
    • About 94.5 percent
    • About 5.5 percent
    • About 10 percent

11. 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

12. 8.

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

    • 2 levels
    • 3 levels
    • 5 levels
    • 4 levels
13. 9.

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

    • 3 levels
    • 5 levels
    • 2 levels
    • 4 levels
14. 10.

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

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