9.1 Levels of Organization
Notes
Ecology is the study of how organisms interact with each other and their environment.
- Levels from smallest to largest: organism → population → community → ecosystem → biome → biosphere.
- A population is one species in one area. A community is all the populations in an area.
- An ecosystem includes the community plus abiotic (nonliving) factors like water, sunlight, temperature and soil.
- Biotic factors are living things.
- A habitat is where an organism lives; its niche is its role (what it eats, when it is active, how it fits in).
Practice
All the bass, frogs, algae, insects and other living things in a pond make up a:
A community is all the different populations living in an area.
Which is an abiotic factor in a forest?
Abiotic factors are nonliving parts of the environment.
An owl hunts mice at night, and a hawk hunts mice during the day in the same field. They share a habitat but have different:
Their roles differ in when they hunt.
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