2. Chapter 2: Living things in ecosystems Section 2.1 – Ecosystems: Everything is connected

3. An ecosystem includes all the different organisms living in a certain area, along with their physical environment.

4. Lagoon Ecosystem

5. Tundra Ecosystem

6. Grassland Ecosystem

7. For convenience ecologists often regard an ecosystem as an isolated unit, but ecosystems usually do not have clear boundaries.

8. Ecosystems are composed of two factors: 1. Biotic Factors

9. Biotic factors are the living parts of the ecosystem – the animals, plants, and microorganisms.

10. Ecosystems are composed of two factors: 1. Biotic Factors 2. Abiotic Factors

11. Abiotic/Biotic Factors

12. Abiotic Factors are the nonliving parts of the ecosystem – rocks, sun, water, weather, temperature, and soil type.

13. There are three levels to ecosystem: 1. Organisms and species

14. An organism is one individual living thing.

15. A species is a group of organisms that are able to produce fertile offspring, and that share common genes and therefore resemble each other.

16. There are three levels to an ecosystem: 1. Organisms and species 2. populations

17. A population is a group of individuals of the same species living in a particular place.

18. There are three levels to an ecosystem: 1. Organisms and species 2. Populations 3. Communities

19. Every population is part of a community, a group of interacting populations of different species.

20. Within the community, all organisms have two unique characteristics.

21. All organisms have a niche – which is their lifestyle.

22. Also, all organisms have a particular habitat – the actual place they live.