biodversity Flashcards
Explain the importance of sampling in measuring the biodiversity of a habitat. (2)
- sample provides estimate
- sample representatve of whole area
Why was it important to take samples in fenced and unfenced areas? (1)
to comapre 2 areas
Explain the difference between species richness and species evenness and why both measurements are needed to assess biodiversity. (3)
- species richness is the number of species in a habitat
- species eveness is the number of individuals in each species in a habitat
- both are needed to reveal dominance
- high biodiversity needs both
Outline the significance of a low value of Simpson’s Index of Diversity. (2)
- habitat dominated by one or few species
- habitat is unstable/ less likey to cope with change
Define the term phylogeny and explain how phylogeny is related to classification. Use the two lynx species as examples. (4)
- phylogeny is the veolutionary relationship between organisms
- phylogeny is the baisis of classification
- example of molecular evidence used to classify
- organisms within the same group have common ancestors
- l,lynx . l patdinus are sufficently different to be palced in seperate species , but simialr to be placed in same genus
Outline three reasons why it is important to conserve the Iberian lynx. (3)
- impact on food chain
- preserving species for future generations
- economic reason e,g tourism
Explain why it is sometimes necessary to conserve a plant species, such as N. thermarum,
outside its natural habitat (ex situ). (3)
- protection from gene
- habitat may be destroyed/ under threat deu to environmental impacts e,g climate change
- protection from predators
- breeding can maintain gene pool
Give three advantages of conserving plant species as seeds and not as adult plants. (3)
- less space taken up so more can be stored
- remaining viable for long periods
- less susceptible to disease
- lower maintenance
Outline an unbiased sampling method that can be used to measure the biodiversity of plant species in grassland. (4)
- use of quadrat
- random sampling
- place at regular intervals along a transect (systematic sampling)
- abundance, count how many plants appear in qudrat or % cover
- repeat many times
- sample at different times/ times of year
Scientists try to estimate the total number of species on Earth.
Suggest three reasons why such estimates are not likely to be accurate. (3)
- not found all species
- many have become extrinct
- some species difficult to distinguish
simpsons index of biodiversity
Outline the implications for a habitat if the Simpson’s Index of Diversity is low. (2)
- habitat is unstable and not able to withstand change
- habitat domianted by one/few species
- change in one species is likley to affect whole habitat
When collecting data on the field trip, the students placed quadrats in 15 locations and calculated a mean number of plants for each species.
-Suggest two other steps they could have taken to ensure that their value for Simpson’s Index of Diversity was as accurate as possible (2)
- random sampling
- survey at different times of year
- standartisation of techniques
Define the term biodiversity. (2)
range of species in an area
a combination od species eveness and richness
Suggest two specific reasons why the government feels it is important to conserve red squirrels in a particular area, such as Northumberland. (2)
- part of food chain
- toruism