Biodiversity Flashcards
What are members of the same species able to do
Capable of breeding to produce fertile living offspring
Binomial system features
Generic name and specific name And based upon Latin and Greek
Generic name
First name and denotes the genus to which an organism belongs
Specific name
Second name and denotes the species to which the organism belongs to
Rules to binomial system
Names in italics or underlined if hand written , first letter of generic system is capital but specific name is lower case , if specific name is not known written as ‘sp’
How do animals distinguish members of their own species
Have same genes so physically look alike and biochemically, behaviours are also alike (influences chances of survival)
Reproduction importance
No individual lives forever so it’s the means by which a species can survive over time
Importance of mating being successful and offspring having max chance of survival
Because most females only produce eggs at certain times of the year
Courtship behaviours enable Individuals to:
Recognise members of their own species(only same species produce fertile offspring) , identify a mate that is capable of breeding, form a pair bond that will lead to success, synchronise mating ( happens when max probablilty of sperm and egg meeting ) , become able to breed( bringing them into physiological state for breeding to occur)
Females can only conceive during a certain short time and only receptive to mating for a time when they produce eggs-how do males determine whether she’s in this stage
Uses courtship behaviour and if she responds w the appropriate behavioural response courtship continues leading to offspring but if she isn’t receptive she shows a different behaviour and he turns his attention elsewhere
How do individuals recognise their partner is of the same species to prepare to mate
Each species has a set again of action between a male and female and this is different for different species
Classification
Grouping of organisms
Taxonomy
Theory and practise of biological classification. Studying the groups of species and their positions in a hierarchal order (taxonomic ranks)
Artificial classification
Divides organisms according to differences that are useful at the time (colour, size, number legs , leaf shape ext) =analogous characteristics
Analogous characteristics
Same function but do not have the same evolutionary origins (wings - birds and butterflies both used for flight but originated differently )
Phylogenetic classification
Evolutionary relationships between organisms and their ancestors and classifies species into groups using shared features derived from their ancestors and then arranged the groups into a hierarchy where the groups are contained within larger composite groups w no overlap
Homologous characteristics (phylogenetic classification based off )
Similar evolutionary origins regardless of their functions in the species ( front leg of horse and arm of human same basic structure and evolutionary origins so are homologous)
Taxon
Each group within a phylogenetic biological classification
Domain
Highest taxonomic rank
3 of the highest taxonomic ranks
Bacteria, archaea(prokaryotes), eukarya
Bacteria and features
Single celled prokaryotes,no membrane-bounded organelles (nuclei or mitochondria), unicellular(cells in clusters or chains tho), ribosomes smaller(70s), cell walls and made of murein, single loop of naked dna made up of nucleus acids not histones tho
Archaea features and how differ from bacteria
Single celled prokaryotes
Differ- genes and protein synthesis more similar to eukaryotes , membranes contain fatty acid chains attached to glyercerol by ether linkages , no murein in cell walls, more complex rna polymerase
Eukarya
Group of organisms made up of one or more eukaryotic cells
Eukarya features
Cells posses membrane bounded organelles(mitochondria and chloroplasts), membranes containing fatty acid chains attached to glycerol by ester linkages , some have cell walls but where they do they have no murein, ribosomes larger (80s) than bacteria and archaea
Eukarya domain divided into 4 kingdoms
Protoctista, fungi, plantae, animalia
In each kingdom the largest groups are called
Phyla
Diversity in each phylum allows it to be divided into
Classes
Each phylum are different to each other by their
Organisms Body plan
Each class is divided into
Orders of organisms that have additional features in common
Each order is divided into
Families
At families the differences are _ obvious
Less
Each family is divided into
Genera
Each genus(genera singular ) divided into
Species
Phylogeny
Evolutionary relationship between organisms( as the hierarchal order of taxonomic ranks is based upon this line of descent of group members)
Phylum
Group of related or similar organisms
Phylogeny of an organism reflects the
Evolutionary branch that led up to it
Phylogenetic relationships of different species represented by
Phylogenetic tree Where the oldest species is at the base of the tree and the most recent ones are at the ends of the beaches
Closer the branches =
Closer the evolutionary relationship
Biodiversity
Term used to describe variety in the living world, the number and variety of living organisms in a particular area
Biodiversities 3 components
Species diversity
Genetic diversity
Ecosystem diversity
Species diversity
Number of diff species and the number of individuals of each species within any one community
Genetic diversity
Variety of genes possessed by the individuals that make up a population of a species
Ecosystem diversity
Refers to the range of different habits from a small local habitat to the whole of the earth
Species richness
A measure of species diversity- the number of diff species in a particular area at a given time (community)
Index of diversity
D=N(N-1) / sum of n(n-1)
N= total No of organisms of all species
n = total No of organisms of each species
Higher the species diversity index = more/ less stable ?
More And is less affected by change
Result of selecting species w particular qualities to make them more productive
No of species and genetic variety of alleles they possess is reduced to the few that have the desired features
Impact of an area being taken up by only 1 species due to an area only being able to support a certain amount of biomass
Smaller area is available for other species so they have to compete for space and resources and many won’t survive the competition
Why are pesticides used to get rid of the unwanted species
As they compete for light water mineral ions and food required by the farmed species reducing biodiversity
Index diversity in agricultural ecosystems
Low
How has food production doubled over the last 40 years
Improved genetic varieties of plant and animal species, greater use of chemical fertilisers and pesticides, use of biotechnology and larger farms and conversion of land to farmland in natural communities
Practices that have directly removed habitats and species diversity
Removal of hedgerows and grubbing out woodland , creating monocultures (replacing meadows with cereal crops or grass for silage) , filling in ponds and draining marshes or wetland, over grazing of land like upland grazing of sheep preventing regeneration of woodland
Other practices having an effect on biodiversity
Use of pesticides and inorganic fertilisers, escape if effluent from silage stores and slurry tanks into water, a sense of crop rotation and lack of intercropping or under sowing
Conservation techniques
Maintain hedgerows at most beneficial height and shape (A better than rectangular), plant hedges not fences , maintain and create ponds and leave wet corners in fields , plant trees on land w low species diversity , reduce pesticides use use organic fertilisers , use crop rotation with a nitgrofen fixing crop not fertilisers to improve soil fertility , use intercropping not herbicides for weed and pest control , create meadows and use hay not grass for silage, leave cutting of field edges and verges until after flowering to allow seed dispersion , have conservation headlands
Conservation headlands
Edges of fields where pesticides are used restrictively so wild flowers and insects can interbreed
Instead of pesticides use
Biological control or genetically modified organisms that are resistant to pests
Conservation methods are more expensive so what’s there to encourage farmers to do them
Financial incentives from department for environment, food and rural affairs and the European Union
Main cause of species loss
Clearance of land to grow crops and meet demand for food from increasing pop
Hedges advantages
Increase species diversity and act as corridors for species to disperse themselves tho , produce food for animals in it and around it
Why are hedgerows removed
Increase in farm machinery and larger farms so small fields not suited to machinery to hedges are removed they also take up land that could produce crops using grants that were set up to increase productive land area
Polyploidy
Organisms have 3 or more sets of chromosomes than usual 2
Non-disjunction
Individual homologous pairs of chromosomes fail to separate during meiosis - results in a gamete having 1 more or less chromosome
