Unit 3 Definitions Flashcards
A group of similar organisms whose members can interbreed in their natural environments to produce viable offspring.
Species
A species role and position in its environment; a species’ interactions with the biotic and abiotic factors of its environment
Niche
Within a species; between individuals of the same species
Intraspecific
Between different species
Interspecific
One species is completely dependent on the other, which is usually harmed
Parasitism
One organism captures, kills and feeds on another
Predation
Necessary and positive association between two organisms
Mutualism
A type of sampling in which a sample is taken of each strata of the population
Stratified sampling
Uses 100 point grid to estimate abundance of a particular species (eg quadrats)
Percentage Cover
The probability that a species will be found within a single quadrat
No of quadrats in which the species is found/total no of quadrats
Percentage Frequency
A measure of the number of species compared to the no. of individuals found in a sample, doesn’t say anything about evenness
S = s √N
Species Richness
How close in numbers each species in an environment is
Evenness (Relative Species Abundance)
A measure of the number of species found in a sample compared with the number of individuals
Species Diversity (Simpsons Diversity Index)
Increase in the size of a population in a particular habitat over time
Population growth
The graphical representation of the change in population density of an organism as it increases rapidly and then stops suddenly, due to environmental or other factors
J-Shaped Population Curve
The graphical representation of the change in population density of an organism when it initially increases slowly and then rapidly as it approaches an exponential growth rate, but then decreased and levels off as the environmental carrying capacity is reached
S-Shaped Population Curve
Organism that eats another living organism (or part of an organism) for nutrition
Consumer
Convert simple inorganic chemicals to complex organic molecules
Producer
Amount of organic matter in a system
Biomass
The total amount of organic matter in an ecosystem produced as a result of photosynthesis
Gross Primary Production (GPP)
Amount of energy available for herbivores in an ecosystem
Net Primary Production
The role and space an organism fills in an ecosystem, including all its interactions with the biotic and abiotic factors of its environment
Niche (Ecological Niche)
The ‘potential’ job of a species resulting from its adaptations/competition with other species
Fundamental Nice
The actual job of a species resulting from its adaptations/competition with other species
Realised Niche
Change and development in plant communities over time to a climax community (hundreds of years).
Primary Succession
Second colonisation event occurring when previous plant community has been destroyed.
Secondary Succession
A double stranded molecule that occurs bound to proteins (histones) in chromosomes in the nucleus, as unbound circular DNA in the cytosol of prokaryotes and in the mitochondria and chloroplasts of eukaryotic cells.
DNA (Deoxyribonucleic Acid)
Protective structures found at the end of chromosomes.
Telomeres