chapter 11 - biodiversity Flashcards
what is habitat biodiversity
number of different habitats found within an area
what are the 2 types of species biodiversity
species richness - number of different species living in a particular area
species evenness - a comparison of number of individuals of each species living in a community
what is genetic biodiversity
the variety of genes that make up a species
what is random sampling
selecting individuals by chance
what is opportunity samping
uses organisms that are conveniently available
what is a con of opportunistic sampling
may not be representative of the population
what is stratified sampling
populations divided into subgroups based on a particular characteristic
what is systematic sampling
sampling different areas of a habitat using line transect or belt transect to see how species change as you move
what is the difference between line transect and belt transect
line transect marks a line along the ground between 2 pole and taking samples at specified points
belt transect provides more information - 2 parallel lines are marked and samples are taken of area between 2 lines
why is a sample never entirely representative of the organisms present in a habitat
sampling bias
chance
what is a pooter
used to catch small insects by sucking on a mouthpiece and drawing insects in
what is a sweep net
used to catch insects in areas of long grass
what is a pitfall trap
catch small crawling invertebrates by digging hole in ground which insects fall into
what is tree beating
white cloth is stretched out under the tree and tree is shaken to dislodge invertebrates
what is kick sampling
studies organisms living in river. The river bed is kicked for a long period of time to disturb substrate and net is held downstream to capture organisms released into flowing water
what is a point quadrat
consists of a frame containing horizontal bar. At set intervals along the bar, long pins can be pushed through the bar to reach ground. Each species of plant the pin touches is recorded
what is a frame quadrat
consists of square frame divided into grid of equal sections
what are the 3 ways of sampling population
density
frequency
percentage cover
what are abiotic factors
non-living conditions in a habitat
what are some abiotic factors
wind speed
light intensity
relative humidity
pH
temperature
oxygen content in water
why is genetic biodiversity important
the more different alleles, the more genetically diverse therefore more likely to adapt to changes in environment so can survive
what increases genetic biodiversity
mutation, creating a new allele
interbreeding between different populations transferring alleles ( gene flow)
what decreases genetic biodiversity
selective breeding
captive breeding programmes
rare breeds
artificial cloning ( asexual)
natural selection
genetic bottlenecks ( alleles survived from sudden event)
founder effect - small number of individuals create a new colony with small gene pool
genetic drift -
what is polymorphic gene
have more than one allele
what is immunoglobin for
plays role in determining blood type
what are the 3 alleles for immunoglobin ( polymorphic gene)
I^A = results in production of antigen A
I^B = results in production of antigen B
I^0 = results in production of neither antigen
what is formula for proportion of polymorphic gene loci
number of polymorphic gene loci/ total number of gene loci
factors affecting biodiversity
deforestation
agriculture
climate change
reasons for maintaining biodiversity
aesthetic reason
economic reasons - soil errosion by deforestation reduces ability to grow crops and feed people
ecological reasons
what is insitu conservation
conservation within natural habitat
what is ex situ conservation
conservation out of the natural habitat
what are insitu ways of maintaining biodiversity
controlled grazing
restricting human access
controlling poaching
feeding animals
reintroduction fo new species
what are methods of ex situ conservation
botanic gardens
seed banks
why may some organisms not be released into the wild
loss of resistance to diseases
behaviour is innate so has to learn behaviour to survive
genetic races - can no longer interbreed with original population
loss of habitat
what is the international union for conservation of nature agreement ( IUCN)
lists details of endangered species and countries work together to conserve these
what is convention on international trades of endangered species ( CITES)
regulates international trade of spcies
what is the rio convention
meeting to create agreements such as convention on biological diversity to develop national strategies for sustainable development to ensure maintenance of biodiversity
what is countryside stewardship scheme
offers payments to farmers to conserve landscape
Aims of the scheme include:
- sustain the beauty and diversity of the landscape
- improving wildlife habitats
- restore neglected lands
- improving opportunities for countryside enjoyment
