Taxonomy And Variation Flashcards
What are the 2 types of variation?
Discontinuous and continuous
Why are there 2 types of variation?
- some characteristics are controlled by only 2 alleles
- but some are controlled by polygenes where each allele has a small effect
What should samples be?
- large enough to be representative of the whole population
- allow statistical tests to be calculated
- but small enough to be practical and fit into the allotted time
- should be collected at random to avoid bias (representative again)
What is biodiversity?
A measure of the variety of living organisms within a particular habitat, ecosystem, biome or in Earth
What is species diversity?
The number of different species within an area
What is ecosystem diversity?
The range of different ecosystems or habitats within a particular area or region
What is genetic diversity?
The number of different alleles of genes in a population
Definition of species
- capable of breeding to produce fertile offspring
- have similar morphology, biochemistry, physiology and behaviour patterns
- have similar genes/DNA and belong to the same gene pool
- occupy the same ecological niche
Order of taxonomic groups
- domain
- kingdom
- phylum
- class
- order
- family
- genus
- species
How to remember the order of taxonomic groups
- dominoes
- king
- prawn
- curry
- or
- fat
- greasy
- sausages
What are the 3 domains?
- bacteria
- archae
- eukaryota
What are the kingdoms?
- animals
- plants
- fungi
- Protista
What is the phylogeny?
The evolutionary relationship between organisms
Shown by a phylogenetic tree
How are phylogenetic trees arranged?
The oldest species at the base and most recent ones at the end of the branches
What is classification by observable statistics?
- traditional method used for classifying organisms
- based on the fact observable characteristics are determined by genes
- limited bc genes can be determined by the environment
- characteristics also determined by polygenes (not distinctly different)
- method not relied upon anymore
What is genetic comparison?
- it is possible to compare the DNA base sequence or amino acid sequences of specific proteins from different organisms
- organisms that are closely related will show more similarities in their DNA base sequences
What is genetic comparison?
- it is possible to compare the DNA base sequence or amino acid sequences of specific proteins from different organisms
- organisms that are closely related will show more similarities in their DNA base sequences
How can genetic comparison happen?
- common protein
- compare base sequence in DNA
- compare base sequence of RNA
- compare sequence of a-a in proteins
- expect that more closely related the species are, the more similar sequences will be
- due to fewer mutations
Suggest why two organisms have the same a-a sequence in their haemoglobin
- derived from a common ancestor
- very closely related
- not long for mutations to occur
How can immunological sequences (reaction to antibodies) be compared?
- pure protein samples extracted from blood of multiple species
- pure samples injected into different rabbits
- each rabbit produces antibodies for that specific protein
- antibodies extracted from rabbits and mixed with protein (antigen) samples
- precipitate (ag-ab complex) from each mixed sample is weighed
How can immunological sequences be interpreted?
- antigen antibody complex causes a precipitate
- more precipitate means there is more reaction
- more reaction means the protein is more complimentary to the antibody
- and so the species are more closely related
What is the purpose of courtship rituals?
- recognise members of your own species (ensure fertile offspring)
- identify a mate that is capable of breeding (sexually mature and receptive)
- form a pair bond (must raise offspring)
- synchronise mating (increase chance of egg and sperm meeting)
- to be able to breed (change in physiological state for breeding to occur)
How are species named?
- each organism has 2 names
- generic name (upper case)
- specific name (low case)
- underlined if written
