8.1.4
Overview of Ecosystems
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Key Terms - Ecosystems
Studying ecosystems is important to understand how the many different organisms interact with each other and their environment. There are some key terms you should know about ecosystems.

Habitat
- The habitat is where an organism lives.
- Different individuals within a species tend to occupy the same type of habitat.
- Individuals in different species are more likely to occupy a different habitat.
- Many species could occupy the same habitat (e.g. thousands of species live in a coral reef habitat).

Ecosystem components
- When many individuals of the same species occupy the same habitat, they are a population.
- Multiple populations of different species in the same habitat form a community.
- A community and the abiotic conditions (e.g. climate) in the environment together form an ecosystem.
- Ecosystems can be huge (e.g. the Amazon Rainforest).
- Ecosystems can be relatively small (e.g. rock pools).

Conditions
- Abiotic conditions are non-living environmental factors.
- E.g. Climate, shade cover.
- Biotic conditions are living environmental factors.
- E.g. Predation, competition.

Niche
- Every species has a specific role in an ecosystem.
- E.g. Decomposing bacteria have the role of breaking down waste material and dead organisms.
- The role is called a niche.

Adaptation
- If an individual is well-suited to surviving in its ecosystem it is said to be adaptive.
- The characteristics of an individual that help it survive and reproduce are adaptations.
1Unity & Diversity - Molecules
1.1Water
1.2DNA Structure & Replication
1.3Transcription & Gene Expression
2Unity & Diversity - Cells
2.1The Origin of Cells
2.2Introduction to Cells
2.3Ultrastructure of Cells
2.4Cell Division
2.5Structure of DNA & RNA
2.6DNA Replication, Transcription & Translation
2.7Cell Respiration
2.8Photosynthesis
2.9Viruses
3Unity & Diversity - Organisms
3.1Diversity of Organisms
3.2Evidence for Evolution
4Unity & Diversity - Ecosystems
4.1Classification
4.3Evolution & Speciation
4.3.1Evidence for Evolution - Fossils & DNA4.3.2Evidence for Evolution - Anatomy & Geography4.3.3IB Multiple Choice - Evidence for Evolution4.3.4Extended Response - DNA & Evolution4.3.5Populations4.3.6Mutations, Genetic Drift, & Gene Flow4.3.7Speciation4.3.8Rate of Speciation4.3.9Allopatric & Sympatric Speciation
4.4Conservation of Biodiversity
5Form & Function - Molecules
6Form & Function - Cells
6.1Membranes & Membrane Transport
6.2Organelles & Compartmentalization
6.3Cell Specialization
7Form & Function - Organisms
7.2Transport
7.3Muscle & Motility
8Form & Function - Ecosystems
8.1Species, Communities & Ecosytems
8.3Carbon Cycle
9Interaction & Interdependence - Molecules
9.1Enzymes
9.2Metabolism
9.3Cell Respiration
10Interaction & Interdependence - Cells
10.1Chemical Signalling
10.2Neural Signalling
10.3Adaptation to Environment
10.4Ecological Niches
11Interaction & Interdependence - Organisms
11.1Integration of Body Systems
12Interaction & Interdependence - Ecosystems
12.1Populations & Communities
12.2Transfers of Energy & Matter
13Continuity & Change - Molecules
13.1DNA Replication
13.2Protein Synthesis
14Continuity & Change - Cells
15Continuity & Change - Organisms
15.1Inheritance
15.1.1Non-Nuclear Inheritance15.1.2Linked Genes15.1.3IB Multiple Choice - Non-Mendelian Genetics15.1.4Extended Response - Inheritance15.1.5Introduction to Non-Mendelian Inheritance15.1.6Chi-Squared Test15.1.7End of Topic Quiz - Inheritance15.1.8Sex-Linked Genes15.1.9Grade 4-5 (Scientific Practices) - Inheritance
16Continuity & Change - Ecosystems
16.1Natural Selection
16.2Stability & Change
Jump to other topics
1Unity & Diversity - Molecules
1.1Water
1.2DNA Structure & Replication
1.3Transcription & Gene Expression
2Unity & Diversity - Cells
2.1The Origin of Cells
2.2Introduction to Cells
2.3Ultrastructure of Cells
2.4Cell Division
2.5Structure of DNA & RNA
2.6DNA Replication, Transcription & Translation
2.7Cell Respiration
2.8Photosynthesis
2.9Viruses
3Unity & Diversity - Organisms
3.1Diversity of Organisms
3.2Evidence for Evolution
4Unity & Diversity - Ecosystems
4.1Classification
4.3Evolution & Speciation
4.3.1Evidence for Evolution - Fossils & DNA4.3.2Evidence for Evolution - Anatomy & Geography4.3.3IB Multiple Choice - Evidence for Evolution4.3.4Extended Response - DNA & Evolution4.3.5Populations4.3.6Mutations, Genetic Drift, & Gene Flow4.3.7Speciation4.3.8Rate of Speciation4.3.9Allopatric & Sympatric Speciation
4.4Conservation of Biodiversity
5Form & Function - Molecules
6Form & Function - Cells
6.1Membranes & Membrane Transport
6.2Organelles & Compartmentalization
6.3Cell Specialization
7Form & Function - Organisms
7.2Transport
7.3Muscle & Motility
8Form & Function - Ecosystems
8.1Species, Communities & Ecosytems
8.3Carbon Cycle
9Interaction & Interdependence - Molecules
9.1Enzymes
9.2Metabolism
9.3Cell Respiration
10Interaction & Interdependence - Cells
10.1Chemical Signalling
10.2Neural Signalling
10.3Adaptation to Environment
10.4Ecological Niches
11Interaction & Interdependence - Organisms
11.1Integration of Body Systems
12Interaction & Interdependence - Ecosystems
12.1Populations & Communities
12.2Transfers of Energy & Matter
13Continuity & Change - Molecules
13.1DNA Replication
13.2Protein Synthesis
14Continuity & Change - Cells
15Continuity & Change - Organisms
15.1Inheritance
15.1.1Non-Nuclear Inheritance15.1.2Linked Genes15.1.3IB Multiple Choice - Non-Mendelian Genetics15.1.4Extended Response - Inheritance15.1.5Introduction to Non-Mendelian Inheritance15.1.6Chi-Squared Test15.1.7End of Topic Quiz - Inheritance15.1.8Sex-Linked Genes15.1.9Grade 4-5 (Scientific Practices) - Inheritance
16Continuity & Change - Ecosystems
16.1Natural Selection
16.2Stability & Change
Practice questions on Overview of Ecosystems
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- 1Which of these is NOT an example of an ecosystem?Multiple choice
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