Populations and Ecosystems Flashcards
Define population
A group of organisms of the same species occupying a particular space at a particular time, that can potentially interbreed
Define community
All the populations of different species living in the same habitat
Define abiotic, give an example
A non living factor in a habitat which can affect a community (eg light intensity)
Define biotic, give an example
A living factor in a habitat that can affect a community (eg predation)
Define habitat
The place were an organism lives
Define ecosystem
The community of organisms together with the non living components of its environment
What are the 4 abiotic factors
Nitrate ion availability
Temperature
Light intensity
Water and humidity
How does the abiotic factor ‘nitrate ion availability’ affect living organisms
It controls the uptake by plants for protein-synthesis and nucleic acid synthesis
How does the abiotic factor ‘temperature’ affect living organisms
Each species has an optimum temperature
If the temp goes above optimum, the tertiary structure is altered
If the temp goes below the optimum, the rate of metabolic reactions will be too slow
Energy is used by the animals to maintain temperature
How does the abiotic factor ‘light intensity’ affect living organisms
Rate of photosynthesis is higher at a high light intensity so therefore the rate of synthesis in organic compounds in plants is higher
How does the abiotic factor ‘water and humidity levels’ affect living organisms
Humidity affects the rate of transpiration in plants
Only xerophytes can survive in dry areas
What is a niche
The role that a species plays within its ecosystems
What is roles are included in a niche (with example of a ladybird)
Where the habitat and organism is - eg on a nettle leaf
How it gets its energy - eg from consuming aphids
How it interacts with other species - eg nettle leaves provide shelter, they are predated by birds
How it interacts with the physical environment - eg tolerates certain temperatures
What do different species occupy? Why is this
Different species occupy different ecological niches. This is because of less competition for resources
Define carrying capacity
The maximum size of a population of a species that an ecosystem can support
Can the numbers of individuals keep increasing indefinitely? Why/why not
The number of individuals in an ecosystem CANNOT continue increasing indefinitely as numbers are limited by biotic and abiotic factors
