Populations Flashcards
Define population
A group of organisms of the same species occupying a particular space at a particular time that can potentially interbreed and produce fertile offspring
Define species
A group of similar organisms that can reproduce to give fertile offspring
Define community
All the populations of different species living and interacting in a particular space at a particular time.
Define gene pool
All the alleles in a population.
Define ecological niche
How an organism fits into the environment, referring to where an organism lives and what is does there
Define ecosystem
Dynamic systems made up of a community and all the non living factors of its environment.
Define allele frequency
How often different alleles occur in the gene pool of a population
Define carrying capacity
The maximum number of individuals of a particular species that the environment can carry and sustain.
List the abiotic factors that could influence the size of a population
- Temperature
The further away the optimum temperature for organisms, the lower the carrying capacity. - Light
The more light the higher the carrying capacity of animals which feed on plants due to increased photosynthesis - pH
A population in which the pH is suited to their optimum enzyme activity has an increased carrying capacity. - Water and humidity
Organisms which survive on little water and dry air would have higher populations than those who don’t.
Define intraspecific competition
When competition occurs within the same species for resources such as food, water breeding sites etc.
Define interspecific competition
When competition occurs with different species for resources such as food, light and water, usually resulting in the growth of one species and the decline of another.
Define the competitive exclusion principle
Where two species are competing for limited resources and the conditions remain the same, the species that uses the resources most effectively will ultimately eliminate the other.