ECOLOGY
Ecosystems
➔ Ecosystem: community + the abiotic factors of the environment
➔ Biome: major type of ecosystem on Earth; position determined by climatic factors like
rainfall + temperature
➔ Community: group of different populations living + interacting within the same area
➔ Population: group of organisms of same species that live in same area at same time
➔ Species: group of organisms that can interbreed + produce viable/fertile offspring
➔ Habitat: place where a species lives
➔ Abiotic factors: all the physical + chemical factors found within an ecosystem
➔ Biotic factors: interactions within same population + between different populations in
the same ecosystem
Energy and Nutrients
● Energy enters ecosystem usually through sunlight
● Nutrients are present + recycled by decomposers
in ecosystem
○ it is still finite and limited though
● Chemical energy is transferred through food chain
○ Light energy converted to chemical energy
in carbon compounds by plants
○ 10% efficiency of energy transferral: 90%
lost in heat and waste
● Energy loss restricts the length of food chains
● Living organisms cannot convert heat to other forms of energy
Food Chains
- Autotrophs: make own food
- Photoautotrophs: using light energy/photosynthesis
- Chemoautotrophs: using chemical energy (ex. bacteria)
- Obtain inorganic nutrients from abiotic environment → nutrient cycling
Ecosystems
➔ Ecosystem: community + the abiotic factors of the environment
➔ Biome: major type of ecosystem on Earth; position determined by climatic factors like
rainfall + temperature
➔ Community: group of different populations living + interacting within the same area
➔ Population: group of organisms of same species that live in same area at same time
➔ Species: group of organisms that can interbreed + produce viable/fertile offspring
➔ Habitat: place where a species lives
➔ Abiotic factors: all the physical + chemical factors found within an ecosystem
➔ Biotic factors: interactions within same population + between different populations in
the same ecosystem
Energy and Nutrients
● Energy enters ecosystem usually through sunlight
● Nutrients are present + recycled by decomposers
in ecosystem
○ it is still finite and limited though
● Chemical energy is transferred through food chain
○ Light energy converted to chemical energy
in carbon compounds by plants
○ 10% efficiency of energy transferral: 90%
lost in heat and waste
● Energy loss restricts the length of food chains
● Living organisms cannot convert heat to other forms of energy
Food Chains
- Autotrophs: make own food
- Photoautotrophs: using light energy/photosynthesis
- Chemoautotrophs: using chemical energy (ex. bacteria)
- Obtain inorganic nutrients from abiotic environment → nutrient cycling
