CLASSIFICATION Flashcards
What kingdom is under the bacteria domain? (1)
Eubacteria
what is the phylogenetic species concept? (1)
defines a species by its evolutionary lineage where two lines diverge sufficiently they are called separate species.
what kingdom is under the archea domain? (1)
archae bacteria
who proposed the three domain model? (1)
Carl Woese in 1990 who suggested a classification system based on RNA.
what kingdom are under the Eukarya domain? (4)
-protista
-plantae
-fungi
-animalia
what is a disadvantage for the biological species concept? (2)
-does not take into account geographical separation
-only applies to organisms that reproduce sexually
what is the biological species concept? (2)
the concept is the most common definition of species. it defines a species as a set of individuals who can reproduce to produce a fertile offspring.
what is a disadvantage of the phylogenetic species concept? (1)
deciding what constitutes sufficient divergence can be a problem.
what is the three domain model? (1)
separates prokaryotes from the archea domain, e.g eukaryotes, archea and prokaryotes (bacteria)
what are the key differences in structure in the 3 domains? (3)
eukarya;
-ribosome: 80s
enzymes: RNA - 12 proteins
bacteria;
-ribsome: 70s
enzymes: RNA - 5 proteins
archea:
-ribosome: 70s
enzymes: RNA - 8-12 proteins
what are some characteristics of the fungal kingdom? (5)
-has a cell wall made of chitin
-are heterotrophic
-most are multicellular (yeast exception)
-reproduce via sporation
-have structures called mycellium
what are some characteristics of the protozoa kingdom? (4)
-mainly single celled or a few cells (cells are not specialised)
-resemble other kingdoms
-protophya resemble plants
-protoza resemble animals
what are some characteristics of the animal kingdom? (4)
-sexual reproduction
-animal cells (dont have a cell wall)
-are motile (except animals such as coral)
-are multicellular heterotrophs
what is the protozoa kingdom? (1)
a group of eukaryotic organisms that do not fit into other kingdoms
what are the 5 kingdoms? (5)
-plants
-animals
-fungi
-protozoa
-prokaryotes
what is the taxonomic hierarchy? (7)
1) domain
2) kingdom
3) phylum
4) class
5) family
6) genus
7) species
what is a eukaryote? (1)
has a membrane bound nucleus (true nucleus)
what are the characteristic of the plant kingdom? (4)
-non motile
-made up of plant cells (have cellulose cell wall)
-they are autotrophs
-mostly multi-cellular - except plants like moss
what is meant by domain? (1)
the type of cell that organisms are made up of, eukaryotic or prokaryotic
what is the binomial name? (1)
the genus and the species of an organism combined
what does taxonomy mean? (1)
is a form of classification that focuses on physical similarities between different species, for ease of naming and identification.
what does classification mean? (1)
the arrangement of organisms into groups or various sizes on the basis of shared features.
what does phylogeny mean? (1)
the classification of organisms by the evolutionary relationship, so that every group shares a common ancestor.
what is an autotroph? (1)
an organism that makes its own food (using energy through the sun)
how do scientists check validity of their results? (3)
scientific journals
peer review
conferences
what is meant by validity? (1)
is about the design of the investigation, controlling variables effectively and being confident that it is the independent variable that is shown to be affecting the dependent variable.
what does the degree of similarity depend on, in DNA hybridisation? (3)
the degree of similarity of samples of DNA from two organisms is disclosed by measuring the temperature are which they separate.
-the more distantly related, the fewer bonds between base pairing
-a lower temperature is then required to separate them.
what is the 1st stage of DNA sequencing? (1)
the DNA molecule is cut into pieces at very specific points by enzymes.
what is the 2nd stage of DNA sequencing? (1)
the pieces of DNA are chemically modified and tagged with florescent dyes, which give a different colour for each base.
what is the 3rd stage of DNA sequencing? (1)
these pieces of DNA are then separated by electrophoresis and the bases recognised by the colour of their florescence.
what is the 4th stage of DNA sequencing? (1)
when the sequence of these pieces of DNA are recorded they are then linked together to make up the base sequence of the whole DNA molecule.
what does the development in the new discipline of bioinformatics exploit? (1)
the fact that organisms that are closely related show fewer differences in the composition of specific acids that they possess.
what occurs in electrophoresis of DNA molecules? (2)
in DNA, phosphate groups in DNA fragments give them a net negative charge. consequently when DNA molecule are placed in an electric field they migrate towards the positive pole.
what is DNA hybridisation? (1)
a technique that involves matching the DNA of different species to discover how closely related they are.
what must be added to make DNA fragments visible on the gel? (1)
a DNA-binding fluorescent dye
why is electrophoresis carried out on agarose gel? (2)
these substances contain tiny pores which allow them to act like a molecular sieve small particles can move through these gels quite easily.
what is DNA sequencing? (1)
the process of determining the exact order of the nucleotides in a DNA molecule.
what are analogous structures? (1)
these resemble each other in function but differ in their fundamental structure.
e.g the wings of bats and birds.
define a species. (1)
a group of living organisms with similar characteristics that interbreed to produce a fertile offspring
how is the relatedness of organisms studied experimentally? (2)
-by DNA hybridisation
-by application of developments in the new discipline of bioinformatics
what is bioinformatics? (1)
he storage, manipulation and analysis of biological information via computer science.
how can DNA be extracted from a tissue sample? (1)
by mechanically breaking up the cells, filtering off the debris and breaking down cell membranes by treatment with detergents.
what is electrophoresis? (1)
a technique of separating charged ions in a flid by applying a potential difference.
how is DNA ‘cut up’? (1)
by addition of restriction endonucleases (restriction enzymes)
what is an important feature of restriction enzymes? (2)
they cut at particular base sequences, there are 2 types, forming either ‘blunt ends’ or ‘sticky ends’ to the cute fragments.
what are homologous structures? (1)
these are structures built to a common plan but adapted for different purposes
e.g the wings of a bird and the arm of a human
what are the main characteristics used to define a species? (3)
-morphology and anatomy (internal and external structures)
-cell structure (eukaryote or prokaryote)
-physiology (blood composition and renal function) and chemical composition (nucleic acids and proteins)
what organisms are in the Protoctista kingdom? (3)
-eukaryotes
-predominately unicellular
-seen as resembling the ancestors of the fungi, plants and animals
what are the 5 kingdoms? (5)
-prokaryotate
-protoctista
-fungi
-plantae
-animalia
what organisms are in the prokaryotae kingdom? (3)
-bacteria
-cyanobacteria (photosynthetic bacteria)
-predominately unicellular organisms
what is phylogeny? (1)
the evolutionary development and history of a species or other groups of organisms
what are the 3 domains? (3)
-archea
-eubacteria
-eukartyota
what organisms are in the animalia kingdom? (3)
-eukaryotes
-multicellular organisms
-motile with heterotopic nutrition
what organisms are in the plantae kingdom? (3)
-eukaryotes
-multicellular organisms
-non motile with autotrophic nutrition
what organisms are in the fungi kingdom? (3)
-eukaryotes
-predominately multicellular organisms
-non motile with histotrophic nutrition
what are the different types of extremophiles? (5)
-halophiles
-alkalinophiles
-acidophiles
-thermophiles
bacteria that thrive in sub zero
