Classification Flashcards
Taxonomy
branch of biology that names and groups organisms, the current term is systematics/cladistics
Morphology
physical characteristics
phylogeny
evolutionary history
history of taxonomy
In the 16th and 17th centuries, many new organisms were discovered. This led to many problems. Common names were used. Those common names changed from location to location, they did not accurately describe the organism, and different species shared the same common names. They began assigning Latin and Greek names.
work of Aristotle
Classified living organisms as either plant or animal (blood or no blood). Grouped those based on land, air, or water dwellers.
why Aristotle’s system became inaccurate
some organisms lived/used multiple of the land, water, and air options, like frogs
work of Carolus Linnaeus
In the 1730s Carolus Linnaeus created a universal system of naming that is still used today. It grouped organisms into hierarchical categories. It went from broad to specific. The system was based on morphology.
work of Carl Woese
Carl Woese used DNA sequencing when he found that there were two very distinct groups of bacteria. So, he proposed that a new domain should be added, Archaea.
when and why did the 5 kingdom system come about
In the 1950s and 60s, they realized the system was failing and in the 1970s the new system was widely accepted. It was changed because most biologists came to the realization that this system failed to accommodate the fungi, protists, and bacteria
What are the 5 kingdoms
Animalia, Plantae, Bacteria, Fungi,, Protista
Linnaeus’ hierarchy system
7 taxa; kingdom, phylum, class, order, family, genus, species; two kingdom; plantae, animalia, broad to specific, morphology
binomial nomenclature
Two part name for each species, universally used, genus name comes first, then species. Genus capitalized, species lowercase. Written underlines, typed italicized
when and why did the domain system come about
In the late 1970s because there were two distinct groups among the prokaryotes, according to genetic makeup. One of the groups produced methane.
phylogenetic tree
shows evolutionary relationships amongst a group of organisms, represents a hypothesis, shows speciation,
evidence used to construct a phylogenetic tree
the fossil record, morphology: comparison of homologous structure, the greater number of similarities close related. embryological development, and shared features.
difference between taxonomy and systematics
taxonomy uses morphology, has a two-kingdom system, and has no domain. Systematics uses phylogeny, a 5-kingdom system, and has domain.
cladistics
based on two principles, clade and derived characters
clade
a group that indicates the common ancestor and all of its descendants, living or non-living
derived characters
a trait that arises within a group of organisms and remains in all descendants, can be lost
node
spot where species break off
Archaea
a domain of archaea that can live in extreme environments, similar to bacteria in some ways
habitats of archaea
extreme environments like hot springs, glaciers, bottom of the sea, acidic water
how were archaea discovered
through Carl Woese’s research
why was rna used by woese
ribosomal rna contains most of the chemical composition and doesn’t change much over time
tree of life general shape
bacteria on one branch, archaea branching off with eukarya on the other side
protist habitats
most habitats are aquatic, freshwater and salt water