C4.2.14—Restrictions on trophic levels
Restrictions on trophic levels explains how energy flow, matter cycling or carbon transfer is represented, measured or limited within ecosystems.
- Syllabus
- First assessment 2025
- Objective
- C4.2.14
- Level
- SL
Exam analysis
Chance of appearing1%of analysed past papers
Latest appearanceNovember 2017
Most common paperPaper1
Typical marks1
Common command terms
- Identify
- Outline
Scoring notes
- Common mistake
- Reversing food-web arrows instead of showing energy transfer direction.
Recent exam appearances
November 2017Paper2 ["SL"] · TZ04(b)[ 1 ]C4.2.14—Restrictions on trophic levels
November 2016Paper1 ["SL"] · TZ018[ 1 ]C4.2.14—Restrictions on trophic levels
Practice this objective
Coverage 2016–2017 · Updated 16 Jul 2026
Concept essentials
- Restrictions on trophic levels must be linked to the correct source, store, transfer or loss process.
- The evidence for restrictions on trophic levels depends on distinguishing energy flow from matter cycling.
- Restrictions on trophic levels is clearer when arrows, units and trophic positions match the biological process.
- Data or diagrams for restrictions on trophic levels need interpretation as ecosystem transfer evidence.