Unit 3 - AOS 1 - CH 1 -Importance of biodiversity Flashcards
Importance of biodiversity
Diversity definition
“Variation of many different types of things or people being included in something”
Biodiversity definition
“Variability of organisms that make up the web of life on earth”
Describe the 3 different types of biodiversity
- Genetic diversity = total amount of genetic info contained in the genes of all organisms on earth
- Species diversity = variety of species on earth
- ecosystem diversity = Variety of habitats, natural communities and ecological processes in the biosphere (e.g. marine)
Importance of genetic diversity
The greater the genetic diversity within a species, the greater the chance of the species long term survival.
Evolution by natural selection
Biodiversity, cause if no inbreeding within a species, overtime species can evolve into separate species, with the different characteristics favoured in their different environments.
Name the 7 factors affecting genetic diversity in populations.
- Mutation and natural selection
- Genetic drift
- Inbreeding
- Extinction
- Genetic swamping
- Demographic variation
- Loss of organisms playing a key role
Describe the factor of ‘mutation and natural selection’
(Factors affecting genetic diversity in populations)
“Individuals with an advantage over others have best chance of surviving thereby passing those off to offspring with their genes.”
Describe the factor of ‘genetic drift’
(Factors affecting genetic diversity in populations)
“Occurs when the allele frequency in a population is determined by random events rather than by natural selection, by chance. “
- Chace -> significant in smaller populations (effects the genetic diversity levels)
Describe the factor of ‘inbreeding’
(Factors affecting genetic diversity in populations)
“Breeding between individuals that are closely related genetically, typically happens in smaller populations.”
Effects = increases the chance of offspring being homozygous and expressing harmful recessive alleles.
Describe the factor of “extinction”
(Factors affecting genetic diversity in populations)
“if changes to enviro are to fast for population to adapt”
Extinction = “complete disappearance of a species or local population”
Rate = not uniform
Describe the factor of ‘genetic swamping’
(Factors affecting genetic diversity in populations)
“Environmental disruption caused by human activities, that may bring populations of a species that once were geographically isolated into contact with a different species’ population.”
Causes hybrid and interbreeding = (breeding different species)
Describe the factor of ‘demographic variation’
(Factors affecting genetic diversity in populations)
Demographic measures = birth rate, death rate, sex ratio.
e.g., population may grow at an average rate over yrs, but any one-time rate may differ from avg, due to particular conditions.
Describe the factor of ‘loss of organisms playing a key role’
(Factors affecting genetic diversity in populations)
“Removal of species that are critical for the survival of other organisms”
- Symbiotic relationship = intimate association
- Symbiosis = Parasitism, commensalism, and mutualism
- Parasitism = organisms (parasite) lives on a host
Definition of ecosystem
Area of abiotic and biotic factors
Ecosystem services
Benefits people obtain from ecosystems
(biodiversity within ecosystems in a source of renewable services that impact our health and wellbeing.)
