Kingdoms and Domains Section 1.4

Learning Goals We are learning the difference between prokaryotes and eukaryotes. We are learning to identify common characteristics between the 6 kingdoms of life.

Kingdoms and Domains Linnaeus originally proposed a two kingdom system: plants and animals but since nobody had microscopes, nobody knew about all of the smallest forms of life biologist then discovered prokaryotes and eukaryotes there has been lots of debate as to how to begin classify organisms at the most general level

Prokaryotic vs. Eukaryotic Cont’d… there has been lots of debate as to how to begin classify organisms at the most general level

Prokaryotic vs. Eukaryotic Cont’d… Eukaryotes Prokaryotes Has membrane bound organelles Has no membrane bound organelles Cellulose based cell wall (where a cell wall is present) Peptidoglycan based cell wall (where a cell wall is present) DNA held on linear chromosomes DNA held on circular chromosomes DNA located within the nucleus DNA contained within the cytoplasm ATP production occurs in mitochondria ATP production occurs in folded regions of the cell membrane called mesosomes Has a nucleus Does not have a nucleus Large ribosomes Small ribosomes Have a phospholipid bi-layer cell membrane May have Flagella there has been lots of debate as to how to begin classify organisms at the most general level

Domains of Life a domain is a new taxonomic rank (highest level) which ALL organisms can be classified into three distinct groups: Eubacteria, Archaea, and Eukaryotes these groups showed significant differences in their genetic makeup, which was very compelling evidence of their distinct evolutionary kinship

Domains of Life Cont’d… Cell Characteristics Other Characteristics Eubacteria prokaryotes unique cell structures, proteins and genetics more ‘primitive’ biochemistry include the traditional bacteria obtain energy in a variety of ways Archaea prokaryotes, though their genes and enzymes behave more like eukaryotes live in extreme and harsh environments (eg. extreme heat) live in anaerobic environments Eukarya eukaryotes can be either unicellular or multicellular can be autotrophs or heterotrophs

Kingdoms of Life this places Eubacteria and Archaea in their own kingdoms along with four separate kingdoms of eukaryotes *Note:* the branches of the phylogenetic tree and the distance between shows an estimate of how closely related the groups are

Common Characteristics of the six kingdoms of Life Eubacteria Cell characteristics: Prokaryotic Cells walls contain a unique compound Cells are variable in shape and size Other characteristics: Diverse means of obtaining food and nutrients All can reproduce sexually Escherichia coli

Common Characteristics of the six kingdoms of Life Archaea Cell characteristics: prokaryotic cell walls and cell membranes have a unique structure most are extremely small Other characteristics: some colonize extreme  environments live in the digestive tracts  of mammals and marine environments all can reproduce asexually extreme thermophiles(organisms that thrive at high temperatures),

Common Characteristics of the six kingdoms of Life Protista Cell characteristics: eukaryotic cells have extreme  diversity of cellular structure some have chloroplasts  and cell walls Other characteristics: May be heterotrophic or  photosynthetic, or both Have variable forms of movement Usually live in aquatic or other  moist environments Reproduce sexually and asexually Amoeba

Common Characteristics of the six kingdoms of Life Fungi Cell characteristics: eukaryotic the cell wall is  composed of chitin most are multicellular cells have no chloroplasts Other characteristics: all are heterotrophic most are terrestrial reproduce sexually and asexually Mushrooms

Common Characteristics of the six kingdoms of Life Plants Cell characteristics: eukaryotic all are multicellular cell walls are composed of cellulose possess chloroplasts Other characteristics: autotrophic and photosynthetic most are terrestrial reproduce sexually and asexually Conifers

Common Characteristics of the six kingdoms of Life Animals Cell characteristics: eukaryotic all are multicellular cells have no cell walls  or chloroplasts Other characteristics: all are heterotrophic most are terrestrial reproduce sexually and asexually Elephants

Check This Out … Endosymbiosis

Learning Goals We are learning the difference between prokaryotes and eukaryotes. We are learning to identify common characteristics between the 6 kingdoms of life.

Homework complete 1.4 questions #1-5