HomeIB ESSTopic 2.1

Individuals, populations, communities and ecosystems

Topic 2.1 covers species classification, population dynamics, and the factors that control population size. Students learn about carrying capacity, S-curves and J-curves, limiting factors, and sampling methods — essential quantitative skills for IB ESS data analysis questions.

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IB ESS · Topic 2.1

Sub-topics in Topic 2.1

2.1.1The biosphere2.1.2Organisms and species2.1.3Classification2.1.4Identification of organisms2.1.5Populations2.1.6Distribution: abiotic and biotic factors2.1.7Abiotic factors2.1.8Niches2.1.9Population interactions2.1.10Carrying capacity2.1.11Density-dependent factors2.1.12Population growth curves2.1.13Limits on human population growth2.1.14Human carrying capacity2.1.15Sampling methods2.1.16Random quadrat sampling2.1.17Capture-mark-release-recapture2.1.18Community2.1.19Habitat2.1.20Ecosystems as open systems2.1.21Sustainability as a natural property of ecosystems2.1.22Human activity and tipping points2.1.23Keystone species2.1.24Biosphere integrity2.1.25Reversing biodiversity loss