1. Warm Up #7
How can you describe an ecosystem?

2. Interactions Within Ecosystems
Lesson 1: Ecosystems

3. Essential Questions How can you describe an ecosystem?
In what ways do living organisms interact?
How do population changes affect ecosystems?

4. Abiotic and Biotic Factors
Ecosystems contain all the nonliving and living parts of the environment in the area
BrainPOP - Ecosystem
Abiotic – nonliving parts of an ecosystem
Ex: sunlight, water, soil, air
Biotic – living or once-living parts of an ecosystem
Ex: trees, ,decaying remains, waste produces, animals

5. What abiotic and biotic factors can you identify? ACTIVITY

6. Habitats, Populations, and Communities
Habitat – the place within an ecosystem that provides the biotic and abiotic factors an organism needs to survive and reproduce
Population – all the organisms of the same species that live in the same area at the same time
Community – all the populations living in an ecosystem at the same time

7. Habitats, Populations, and Communities
How do populations and communities compare and contrast?

8. Interactions of Living Things
Niche – the way a species interacts with abiotic and biotic factors to obtain food, find shelter, and fulfill other needs
Predation – the act of 1 organism (predator) feeding on another organism (prey)
Symbiosis – a close, long-term relationship between 2 or more species that usually involves an exchange of food or energy
Competition – interactions between 2 or more organisms that need the same resource at the same time

9. Symbiosis Mutualism – both species benefit from the relationship
Commensalism – 1 species benefits from the relationship and the other isn’t harmed or helped
Parasitism – 1 species (parasite) benefits
and the other (host) is harmed

10. Population Changes
Populations increase when offspring are produced or new individuals move into a community
Populations decrease when individuals die or more away
Population density – the size a population compared to the amount of space available
High = individuals live closer together
Low = individuals live further apart

11. Population Changes
Carrying capacity – largest number of individuals of 1 species that an ecosystem can support over time
Depends on abiotic and biotic factors
What happens if a population exceeds its carrying capacity?
Extinction of 1 population can affect other populations

12. Population Changes Interpret the graph
What information is being presented?
What units are being used in the graph?
What happens to the moose population as the wolf population increases?
What is the maximum population size for the wolves and moose?