Species and Taxonomy: Flashcards
Species
Organisms are capable of breeding to produce living, fertile offspring.
Binomial system
first name - genus (first letter of the work upper case) and second name - species
Courtship behaviour:
Individuals can, therefore, recognise members of their own species by the way they act. The ability to display a behaviour is genetically determined.
What is the purpose of courtship behaviour?
Recognise members of their own species, identify a mate that is capable of breeding, form a pair bond, become able to breed, synchronise mating.
What is artificial classification?
Divides organisms according to differences that are useful at the time. Some features may include colour, size and number of legs.
What is phylogenetic classification?
Based upon the evolutionary relationship between organisms and their ancestry, species are grouped using shared features derived from their ancestors
What is phylogenetic classification partly based on?
Homologous characteristics have similar evolutionary origins regardless of their functions in the adult of a species
What is a taxon?
Each group within a phylogenetic biological classification
What is Taxonomy?
The study of these taxons and their positions in a hierarchical order, and these are known as taxonomic ranks
What are 3 domains?
Bacteria, Archaea (a group of prokaryotes) and Eukarya
What is the bacteria domain?
A group of single-celled prokaryotes.
What are the Archaea?
A group of single-celled prokaryotes that were originally classified as bacteria, which they resemble in appearance.
How does Archaea differ from bacteria?
There is no meurin in cell walls, their genes and protein synthesis more similar to euakryotes, they have more complex form of RNA polymerase
What is the Eukarya domain?
A group of organisms made up of more eukaryotic cells
What is phylogeny?
This evolutionary relationship between organisms
What is biodiversity?
General term used to describe variety in the living world
What is species diversity?
Refers to the number of different species and the number of individuals of each species within any one community
What is genetic diversity?
Refers to the variety of genes possessed by the individuals that make up the population of a species
What is ecosystem diversity?
Refers to the range of different habitats from a small local habitat to the whole of the earth
What is species richness?
The number of different species in a particular area at a given time (community).
Agricultural ecosystems are controlled by humans and farmers select for particular qualities. As a result, the number of species and the genetic variety of alleles they possess is ________ to the few that exhibit the desired features.
a. reduced
What are some farming practices that diminish variety?
> Remeoval of hedgerows and grubbing out woodland
Creating monocultures, for example, replacing natural meadows
Filling in ponds and draining marsh and other wetland
Overgrazing of land -> preventing regenerating of woodland
What are some conservative techniques?
> Maintain hedge browns
Crop rotation that includes a nitrogen-fixing crop
Use intercropping rather than herbicides to control weeds and other pests
Comparison of observable characteristics:
> Genetic diversity was measured by observing the characteristics of organisms. The method is based on the fact that each observable characteristic is determined by a gene or genes. Observable characteristics have their limitations because a large number of them are coded for more than one gene.
Comparisons of DNA base sequences:
Comparison of the base sequence of mRNA: complimentary to those of the strand of DNA from which they were base
Comparison of amino acid sequence in proteins: genetic diversity within, and between, species can therefore be measure by comparing the amino acid sequence of their proteins
Why might ordinary sampling be ineffective?
Sampling bias: The selection process may be biased. The investigators may be making unrepresentative choices
Chance: Even if sampling bias is avoided, the individuals chosen may be, by pure chance, not be representative
What can be done to remove chance from the sampling process?
Using a large sample size
