topic 4B Flashcards
define taxonomy
The scientific way of describing as as classifying and naming organisms.
biodiversity
a measure of the variety of living organisms and their genetic differences
evolution
the process by which natural selection acts on variation to bring about adaptations and eventually speciation
morphology
the study of the form and structure of organisms
analogous features
features that look similar or have a similar function, but are not from the same
biological origin
homologous structures
structures that genuinely show common ancestry
domains
the three largest classification categories: the Eukaryota, the Bacteria and the Archaea
kingdom
the classification category smaller than domains; there are six kingdoms: Archaebacteria,
Eubacteria, Protista, Fungi, Plantae and Animalia
species
a group of closely related organisms that are all potentially capable of interbreeding to produce
fertile offspring
Archaea
domain made up of bacteria-like prokaryotic organisms found in many places including extreme
conditions and the soil; they are thought to be early relatives of the eukaryotes
Archaebacteria
ancient type of bacteria found in many different environments
Eubacteria
true bacteria
Protista
contains all single-celled organisms, green and
brown algae and slime moulds
Fungi
eukaryotic kingdom of heterotrophs with chitin in their cell walls
Plantae
a mainly autotrophic eukaryotic kingdom containing mosses, liverworts, ferns, gymnosperms and
angiosperms (the flowering plants)
Animalia
a mainly heterotrophic eukaryotic kingdom including all the invertebrates and vertebrates
morphological species model
a species definition based solely on
the appearance of the organisms observed
sexual dimorphism
describes species where there is a great deal of
difference between the appearance of the male and female
molecular phylogeny
the analysis of the genetic material of
organisms to establish their evolutionary relationships
ecological species model
a species definition based on the
ecological niche occupied by an organism
mate-recognition species model
a species definition based on
unique fertilisation systems, including mating behaviour
genetic species model
a species model based on DNA evidence
DNA sequencing
he process by which the base sequences of all or
part of the genome of an organism is worked out
DNA profiling
he process by which the non-coding areas of DNA
are analysed to identify patterns
gel electrophoresis
a method of separating fragments of proteins or
nucleic acids based on their electrical charge and size\
also a example of molecular phylogeny.
phylogenetic tree
model used to show the relationships between
different groups of organisms
endosymbionts
organisms that live inside the cells or the body of another organism
Monera
a kingdom in the five-kingdom classification system that
contains the Archaea and Eubacteria
genus
organisms are very similar and most likely have a common ancestor
models for defining species
- The morphologiacl concept species
- Biological species concept
- ecological species model
- mate-recognition species model
- genetic species model
limitations on why it cans be concept 1 and example
due to huge variations within a group of closely related organisms, the difference can be confused as a diff species
example sexual dimorphism, diff between male and female peacocks
limitations concept 2 and example
- not all organisms ins a species live in the same area and therefore, will not interbreed.
examples lions and tiger breed, most offsprings they make can beed as well.
limitation on why concept 3 cannot be correct and example.
definition of ecological niche varies.
occupy different ecological niches.
sharing ecological roles
limitations on why it cans be concept 4 and example
poorly understood mating behaviours,
overlapping of mating systems.
crossbreed and cross- pollination to produce a offspring.
limitations on why it cans be concept 5 and example
hybrid organisms can complicate analysis due to overlapping.
expensive to much man power and hour.
molecular phylogeny
developments in RNA/DNA analysis and protein analysis have led to the identification of the relationships between between organisms.
why is molecular phylogeny used
- larify the relationship/ classification of organisms based on the models defining species
- identifying species
- trace development pathway
limitation for molecular analysis.
- dependent of technology and can be labour intensive.
- understanding of entire genomes is still incomplete,
defining endosymbiosis
is where a cell lives inside another cell resulting in a mutual benefit.
the endosymbiosis theory
explains how mitochondria and chlorophyll are engulfed into the cell.
