IB Biology D4.2 Definitions
This page contains our IB Biology definitions for D4.2. By learning each one of these definitions, you will fully cover the content for IB Biology 'Stability & change'.
bioaccumulate
The process by which toxins are passed up the trophic levels of an ecosystem, concentrating within the organisms they are passed to.
Biomagnification
The process by which toxins are passed up the trophic levels of an ecosystem, concentrating within the organisms they are passed to.
ecosystem
The interaction of a community with its abiotic environment
eutrophication
The dense plant and algal growth due to nitrates that uses up all oxygen and suffocates other life
keystone species
Species within an ecosystem which play an integral role, without which the ecosystem would fail to exist.
mesocosm
An artificial mini-ecosystem
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