Energy Flow Through Ecosystems

AP Biology· difficulty 2/5

The pyramid below shows energy stored at each trophic level (kJ/m^2/yr) in a grassland ecosystem.

Producers: 20,000 kJ Primary: 2000 kJ Secondary: 200 kJ Tertiary: 20 kJ

Roughly what percent of energy is transferred between trophic levels?

  • A

    About 90 percent

  • B

    About 50 percent

  • C

    About 1 percent

  • D

    About 10 percent

    check_circle

Explanation

Each level retains roughly 10 percent of the level below (20000 -> 2000 -> 200 -> 20), consistent with the standard 10 percent rule.

Want 10 more like this — adaptive to your weak spots?

Related questions