Classification and Three Domains of Life
Archaea. Prokaryotes
Archaea: -Prokaryotic, unicellular organisms -Lack a membrane-bounded nucleus -Reproduce asexually many are autotrophic by chemosynthesis; some are heterotrophic by absorption -unique rRNA base sequence -Distinctive plasma membrane and cell wall chemistry
Who is Aristotle and how does he relate to classification?
Aristotle is a greek philosopher who devised the first known classification system. He grouped animals by whether they flew, swam, or walked.
What are the three domains of life?
Bacteria, Archaea and Eukarya are the three domains of life.
Bacteria. Cyanobacteria
Bacteria: -Prokaryotic, unicellular organisms -Lack a membrane-bounded nucleus -Repoduce asexually -Heterotrophic by absorption -Autotrophic by chemosynthesis or by photosynthesis -Moved by flagella Hetertrophic bacteria
Why do we use binomial nomenclature?
Because all organisms are given a universal name (every foreign country uses the same name)
What are the names of the taxons in order from broadest to most specific?
Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species
What is the acronym for remembering the taxons?
Dumb King Phillip Came Over From German Soil
What are the three domains?
Eukarya, Eubacteria or Bacteria, Archaebacteria
Eukarya. Eykaryotes
Eukarya: -Eukaryotic, unicellular to multicellular organisms -Membrane-bounded nucleus -Sexual reproduction -Phenotypes and nutrition are diverse -Each kingdom has specializations -Flagella, if present, have a 9+2 organization
How are scientific names written in binomial nomenclature?
Genus name followed by species name Genus is capitalized, species is lowercase Entire name is italicized
These domains are based on:
The cellular composition of organisms. Archaea are the smallest and simplest types of cells, those without a nucleus.
What is taxonomy?
The science of classification
Why do we classify?
To study the diversity of life and group organisms in a logical manner
How do we classify organisms now (present time)?
We use Linnaeus's system but add comparison of body chemistry and development features (ex. DNA sequence and analogous structures.)
Sometimes organisms look similar but are not related Why?
convergent evolution
What is a taxon?
A group or level of organization
What is classification?
A system that groups organisms based on common features they share
What is binomial nomenclature?
A two name naming system
What does it mean to be the most specific level of classification?
It's more exclusive, only one type of species is in this category
What does it mean to be the broadest level of classification?
Many different organisms fit into the category
What are the four kingdoms in the Eukarya domain?
Protista, Fungi, Plantae, and Animalia
