Ecology Basics

Study Notes

Definition: The study of the interactions between organisms and their environment
Levels of Organization:
1. Organism: Individual living thing
2. Population: Group of organisms of the same species in a specific area
3. Community: Group of different species in a specific area
4. Ecosystem: Community and its physical environment
5. Biosphere: All ecosystems on Earth
Ecosystem Components:
- Biotic Factors: Living components (organisms)
- Abiotic Factors: Non-living components (water, temperature, light)
Ecological Relationships:
- Predation: One organism captures and consumes another
- Symbiosis: Close, long-term relationship between two species
  - Mutualism: Both species benefit
  - Commensalism: One species benefits, the other is unaffected
  - Parasitism: One species benefits, the other is harmed
Ecological Succession:
- Primary Succession: New habitat formation (e.g., volcanic island)
- Secondary Succession: Habitat disruption (e.g., forest fire)

Definition: The study of the functions and processes that occur within living organisms
Cellular Physiology:
- Cell Membrane: Semi-permeable membrane controlling what enters/leaves the cell
- Cellular Transport: Movement of molecules across the cell membrane
  - Passive Transport: No energy required (diffusion, osmosis)
  - Active Transport: Energy required (pumps, carrier proteins)
Organ Systems:
- Nervous System: Controls and coordinates body functions
- Circulatory System: Transports oxygen and nutrients to cells
- Respiratory System: Exchanges oxygen and carbon dioxide
- Digestive System: Breaks down and absorbs nutrients
Homeostasis: The ability of an organism to maintain a stable internal environment despite changes in the external environment
- Negative Feedback: Counteracts changes to maintain homeostasis
- Positive Feedback: Amplifies changes to achieve a specific response

Definition: Study of interactions between organisms and their environment
Levels of Organization:
- Organism: Individual living thing
- Population: Group of organisms of the same species in a specific area
- Community: Group of different species in a specific area
- Ecosystem: Community and its physical environment
- Biosphere: All ecosystems on Earth
Ecosystem Components:
- Biotic Factors: Living components (organisms)
- Abiotic Factors: Non-living components (water, temperature, light)
Ecological Relationships:
- Predation: One organism captures and consumes another
- Symbiosis: Close, long-term relationship between two species
  - Mutualism: Both species benefit
  - Commensalism: One species benefits, the other is unaffected
  - Parasitism: One species benefits, the other is harmed
Ecological Succession:
- Primary Succession: New habitat formation (e.g., volcanic island)
- Secondary Succession: Habitat disruption (e.g., forest fire)

Definition: Study of functions and processes within living organisms
Cellular Physiology:
- Cell Membrane: Semi-permeable membrane controlling what enters/leaves the cell
- Cellular Transport: Movement of molecules across the cell membrane
  - Passive Transport: No energy required (diffusion, osmosis)
  - Active Transport: Energy required (pumps, carrier proteins)
Organ Systems:
- Nervous System: Controls and coordinates body functions
- Circulatory System: Transports oxygen and nutrients to cells
- Respiratory System: Exchanges oxygen and carbon dioxide
- Digestive System: Breaks down and absorbs nutrients
Homeostasis:
- Definition: Ability of an organism to maintain a stable internal environment
- Mechanisms:
  - Negative Feedback: Counteracts changes to maintain homeostasis
  - Positive Feedback: Amplifies changes to achieve a specific response