Biodiversity Flashcards
Genetic diversity
Total number of alleles in a population
Species definition
The ability to produce offspring that are able to reproduce.
Risk of low genetic variation
Small gene pool more susceptible to extinction due to an environmental change
Species richness
Number Of different species present in an area
Species evenness
The relative abundance of species in an area
The index of diversity/ Simpsons reciprocal index
Formula given
Describes the relationship between number of species in community and the number of individuals in a species
High value = many niches and low competition
Low value = few niches, domination of species and competition is higher
Hierarchy definition
Smaller groups within groups and are non - overlapping
Each group in phylogenetic classification is called a
Taxon
Taxa (plural)
Taxa names (use acronym)
Domain Kingdom Phylum Class Order Family Genus Species
How is each species universally identified by a binomial
Genus
Species
If handwritten must be underlined, if those must be in italics
Can you explain how advances in immunology and genome sequencing help clarify evolutionary relationships between organisms?
Sequence of bases - more differences in sequence of bases likely mean farther their common ancestor is
Non - coding sequences of DNA provide the best means of comparison as more mutations will occur readily here - natural selection means that most genes in extrinsic have to be the same as a functional protein will be formed
Domains are
Bacteria
Archaea
Eukarya
Species diversity
Refers to the number of different species and the number of individuals of each species within any one community
Ecosystem diversity
Range of habitats from a small local habitat to the whole earth
Biodiversity definition
Species diversity, Genric diversity and ecosystem diversity
Phylogenetic class system based on three things
Evolutionary relationships
Hierarchy - smaller groups wishing groups with no overlap
Grouped species using shared characteristics from a common ancestor
Three ways to investigate diversity
Comparison of base sequences
Comparison of mRNA
Comparison of amino acids sequences
Why is courtship behaviour a necessary precursor to successful mating? (4 reasons)
To recognise members of their species to produce fertile offspring
To identity a male that is capable of breeding
To form a pair bond that’ll lead to successful mating and raising of offspring
To synchronise mating so that it occurs when there’s maximum possibility of sperm and egg fusion
Can you explain the role of courtship in species recognition?
Important in species recognition as meme era of a species are able to recognise each other and hence successfully reproduce so that energy is not wasted in sterile offspring that can not pass DNA to next generation and ensure SPECIES SURVIVAL
Before genetic sequencing technology how were animals classified?
Based on observable characteristics and common features however these are controlled by several genes and can often be affected by the environment. Continue variation can be difficult to distinguish and categorise.
Can you explain how farming techniques reduce biodiversity?
Removal of hedgerows so that more space for farming machinery - affects habitat of many organisms inside and often pollinators
Creating monocultures by replacing large meadows with one crop - on species only
Filling in ponds and wetlands - many organisms in ponds die
Overgrazing of one by sheep - prevents regeneration of woodland
Eutrophication - overuse of fertilisers to increase yield resulting in run off into streams and ponds. Forms algae on too which prevents light reaching seaweed and other organisms at the bottom
Impact of agriculture
Malthus theory that population will grow exponentially and exceed linear increase of resources leading to a population crash
Can you explain the balance between conservation and farming?
Prevent diminishing the variety of habitats within ecosystems and consequently reduce species diversity
Problem of monoculture and solution
Land only used for one species of crop
Crop rotation - planting nitrogen fixing crop after certain crop can ensure less fertilisers are needed
Intercropping - two species of crop in one land living together, so also more organisms
