B6 Classification (page 81) Flashcards
What is Classification?
it is organising Living Organisms into Groups.
When was organisms traditionally been classified and by whom?
they have been classified according to a system first proposed in the 1700’s by Carl Linnaeus.
it groups living things according to their characteristics and the structures that make them up.
In the system (see diagram on page 81), what is the system called, and what is it showing?
The system is known as the ‘Linnaean System’
It shows living things are first divided into Kindoms (e.g. the plant kingdom).
Has Classification Systems changed or stayed the same over the years?
They have changed over time.
How has Classification systems changed over time?
As knowledge of the biochemical process - taking place inside organisms developed and microscopes improved, (which allowed us to find out more about the internal structures of organisms)
Scientists put forward new models of classification.
Who proposed the ‘Three-Domain System in 1990, and why?
Carl Woese proposed the three-domain system.
By using evidence gathered from new chemical analysis techniques such as RNA sequence analysis, he found that in some cases, species thought to be closely related in traditional classification systems are in fact not as closely related as first thought.
(RNA is a single strand of DNA)
What is the Three Domain System?
it is where organisms are split into three large groups called domains.
What are the three large domains called?
1) Archaea
2) Bacteria
3) Eukaryota
What is Archaea Domain?
Organisms in this domain are primitive bacteria. They’re often found in extreme places such as hot springs and salt lakes.
What is Bacteria domain?
This domain contains true bacteria like E.coli and Staphylococcus. Although they often look similar to Archaea, there are lots of biochemical differences between them.
What is Eukaryota doman?
This domain includes a broad range of organisms including fungi (page 43), plants, animals and protists (page 43).
The Three large domain groups, are then subdivided into what?
they are subdivided into smaller groups
Kingdom
Phylum
Class
Order
Gamily
Genus
Species.
Organisms are names according to the what?
Binomial System.
In the Binomial System, every organism is given its own two-part what name?
two-part latin name.
The first part refers to the genus that the organsim belongs to. (this gives you information on the organism’s ancestry)
The second part refers to the species. (e.g. humans are known as Homo Sapiens, ‘Homo’ is the genus and ‘sapiens’ is the species)
What is the Biomial System?
it is used worldwide and means that scientists in different countries or who speak different languages all refer to a particiular species by the same name - avoiding potential confusion
