CourseCourse QuestionQuestion

IB Environmental Systems and Societies

Topic 1: Foundation

Topic 2: Ecology

2.1 Individuals, populations, communities, and ecosystems

2.2 Energy and biomass in ecosystems

2.2.1—Ecosystem sustenance

2.2.2—First law of thermodynamics

2.2.3—Energy and matter transformation

2.2.4—Photosynthesis

2.2.5—Producers

2.2.6—Cellular respiration

2.2.7—Heat generation

2.2.8—Second law and energy loss

2.2.9—Consumer energy sources

2.2.10—Producers and food chains

2.2.11—Food chains and trophic levels

2.2.12—Food-chain energy losses

2.2.13—Gross and net productivity

2.2.14—Limits on trophic levels

2.2.15—Food webs

2.2.16—Biomass measurement

2.2.17—Ecological pyramids

2.2.18—Non-biodegradable pollutants

2.2.19—Microplastics

2.2.20—Human activity impacts

2.3 Biogeochemical cycles

2.4 Climate and biomes

2.5 Zonation, succession and change

Topic 3: Biodiversity and conservation

Topic 6: Atmosphere and climate change

Topic 7: Natural resources

Topic 8: Human populations and urban systems

IB/ESS/SL//Concept/Topic 2: Ecology/2.2 Energy and biomass in ecosystems/2.2.10—Producers and food chains

Topic 2: Ecology

Syllabus: First assessment 2026
Section: —
Level: SL

Exam analysis

Most tested topics

Individuals, populations, communities, and ecosystems
Energy and biomass in ecosystems
Biogeochemical cycles
Climate and biomes
Zonation, succession and change