Ecology and energy transfers (5.1-5.4, 5.10-5.11, 5.21) Flashcards
(37 cards)
Ecosystem
All the organisms and abiotic factors living in a particular area
Habitat
The place where an organism lives
Population
All the organisms of one species in a habitat
Population size
The number of individuals of one species living in a particular area
Community
All the organisms of different species living in the same habitat which interact with each other
Abiotic factors
Non living features of an ecosystem
Biotic factors
Living features of a ecosystem
How does temperature as an abiotic factor increase population size
If temp is ideal for the mammal then they don’t need to use up energy in metabolic reactions to maintain their body temp, and can instead use it for growth and reproduction
How can temperature as an abiotic factor decrease population size
If temp is lower or higher than optimum body temp then the mammal has to use lots of energy to maintain the correct body temperature. Less energy can be used for reproduction and growth, so population size will decrease
Interspecific competition
Where organisms of different species compete for same resources
Intraspecific competition
When organisms of the same species compete for the same resources
Carrying capacity
The maximum stable population size of a species an ecosystem can support
Distribution because of abiotic factors
Where non living factors affect where an organism is situated
Eg. Some plants only grow on south facing slopes in the Northern hemisphere because light intensity is the greatest
Distribution because of biotic factors
In interspecific competition there is a species that is likely to be outcompeted and wont be able to survive alongside the other species
Niche
The role/position of a species in an ecosystem
How niche accounts for abundance of species
Two species occupying similar niches will compete, so fewer individuals of each species will be able to survive in that area
How niche accounts for distribution of species
Organisms can only survive in a habitat where all conditions that make up their role exist
Abundance
The relative representation of a species in an ecosystem
Succession
The process of an ecosystem changing over time
Where does primary succession occur
On newly formed or exposed land
Eg. Bare rock
Where does secondary succession occur
Land that’s cleared of all plants so only soil remains
Process of succession
- Primary succession occurs where a pioneer species arrives
- Pioneers change the abiotic conditions by breaking up rock and forming soil which is suitable for other species like moss
- The moss dies and decomposes, making ti more suitable for shallow plants to grow
- Secondary succession then occurs
- Larger plants outcompete the existing community as they are better adapted and become the dominant species
- Ecosystem become more complex, with biodiversity increasing
- Climax community is reached
Pioneer species
The first organisms to colonise the newly exposed land which can withstand the harsh environment
Climax community
The final stage of succession where the conditions are stable
