Unit B


The Earth's ecosystems are a delicately balanced network of living and non-living factors. The organisms that live within these ecosystems are sensitive to change in the non-living environment. Field researchers study the health of ecosystems by collecting data on the organisms and characteristics of ecosystems. Given long periods of time, populations adapt and change. There is ample evidence of the changing ecosystems that provide clues to the mechanisms for change.

By marcelokato [CC0], via Pixabay

Big Ideas

This unit consists of two modules. These modules will investigate ecosystems and the living and non-living factors within an ecosystem. The classification of organisms will be explained and applied in a field study. The unit investigates the change in populations over time.

Specifically, you should be able to

  • describe how the biosphere is composed of ecosystems, each with distinctive biotic and abiotic characteristics
  • explain the mechanisms involved in the change of population over time

In This Unit

This unit is organized into two modules
  1. Module 3 - Ecosystems
  2. Module 4 - Population Change


Each module has three assignments that are listed on the module introduction page. At the end of the unit, write the Unit B Test.

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