10.Biodiversity Flashcards
Define species
A group of similar organisms that can breed together to produce fertile offspring
How are species named
- generic name (genus)
- specific name (species)
What does courtship behaviour enable
- individuals can recognise members of their own species (to ensure fertile offspring)
- identify a mate that is capable of breeding (to ensure partner is sexually mature and fertile)
- form a bonding pair (ensure mating and successful raising)
- synchronise mating (maximum probability of fertilisation)
Name the two forms of classification
- artificial classification
- phylogenetic classification
What is artificial classification
Divides organisms according to differences that are useful at the time
What is phylogenetic classification
- is based upon evolutionary relationships between organisms and their ancestors
- classifies species into groups using shared features derived from their ancestors
- arranges the groups into hierarchy in which groups are contained within larger composite groups with no overlap
Name the ranks of the classification system
- kingdom
- phylum
- class
- order
- family
- genus
- species
Define species diversity
The number of different species and the number of individuals of each species within any one community
Define genetic diversity
The variety of genes possessed by the individuals that make up a population of a species
Define ecosystem diversity
Refers to the range of different habitats
What is species richness
This is the number of different species in a particular area at a given time
What does the index of diversity equation use (d, N, n)
d=index of diversity
N=total number of organisms of all species
n=total number of organisms of each species
Name some ways agriculture has directly reduced species diversity
- removal of hedgerows and woodland
- creating monocultures (eg wheat)
- filling in ponds and draining marsh and other wet land
- over-grazing of land preventing regeneration of woodland
Name some ways agriculture has indirectly reduced species diversity
- use of pesticides and inorganic fertilisers
- escape of effluent and slurry
- absence of crop rotation and intercropping
Name some example techniques of conservation used in agriculture
- maintaining hedgerows/ using hedges instead of fences
- maintain existing ponds
- leave wet corners of field
- plant native trees on land with low species diversity
- use a nitrogen fixing crop in rotation
In what ways can genetic diversity be measured within and between species to help scientists determine evolutionary relationships
- comparison of observable characteristics
- comparison of DNA base sequences
- comparison of mRNA base sequence
- comparison of amino acid sequences in proteins
Describe how the comparison of observable characteristics can help scientists determine evolutionary relationships
- observable characteristics are determined by genes (to see genetic similarities)
- limited as characteristics are polygenic so hard to distinguish one gene from another
Describe how the comparison of DNA base sequences can help scientists determine evolutionary relationships
- using new gene technology we can now read the base sequences of the DNA of any organism (to see genetic similarities)
- limited as species evolve due to mutations making their DNA look less closely related
Describe how the comparison of mRNA base sequences can help scientists determine evolutionary relationships
-mRNA is complementary to DNA so same reasons as DNA
Describe how the comparison of amino acid sequences in proteins can help scientists determine evolutionary relationships
-amino acid sequence is determined by mRNA with in turn is determined by DNA. This way base sequences of DNA can be found (to see genetic similarities)
Name steps involved in a quantitative investigation
- collection of data via random sampling
- analyse using statistical test
- calculate the mean and standard deviation
- large deviation means lots of variety
Describe how you would carry out a collection of data via random sampling for a quantitative investigation
- divide area into grid with numbered lines
- use random number generator for coordinates
- take samples with quadrat at these coordinates
- use large sample size (say number)
