Grade 6 · Science · Lesson 21

Ecosystems, Populations and Carrying Capacity

Look out the window. A bird flies past. A tree drops a leaf. Ants march along the ground, and somewhere underneath, fungi are quietly breaking that leaf back into soil. None of those living things is alone. Each one belongs to a population, and every population is tangled up with every other one in a single living system called an ECOSYSTEM. In this lesson we will learn how to talk about ecosystems like a scientist: who lives there, how they make a living, and why no place can hold an unlimited number of any one species.

What this lesson teaches

1Define ecosystem, population, community, habitat, and niche using clear examples
2Classify living things as producers, consumers, or decomposers based on how they get energy
3Explain what carrying capacity means and the limits that set it
4Predict what happens to a population when resources rise or fall

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