Download Chapter 10 Lecture Notes

Chapter 10—Classification of Microorganisms.
I.
II.
The Study of Phylogenetic Relationships.
a. Taxonomy.
i. The science of classifying organisms, based on common physical characteristics.
ii. Provides universal names for organisms.
iii. Provides a reference for identifying organisms.
b. Systematics or phylogeny.
i. The study of the evolutionary history of organisms; descent from a common ancestor.
c. The Three-Domain System. Fig. 1.
i. Endosymbiotic Theory. Figs. 2 and 3.
d. Phylogenetic Hierarchy.
i. Descent from a common ancestor; based on common properties in genetics, fossil
structure, etc.
Classification of Organisms.
a. Scientific Nomenclature.
i. Established by Linnaeus in 1735
ii. Binomial nomenclature.
1. Genus and specific epithet.
b. Taxonomic Hierarchy. Fig. 5.
i. Domain, Kingdom, Phylum (Division), Class, Order, Family, Genus, Species.
c. Classification of Prokaryotes.
i. Based on rRNA sequence similarities.
ii. Prokaryotic species: A population of cells with similar characteristics.
1. Clone: Population of cells derived from a single cell.
2. Strain: Genetically different cells within a clone.
d. Classification of Eukaryotes.
i. Eukaryotic species: A group of closely related organisms that breed among themselves.
ii. Domain Eukarya: (See Chapter 1 notes).
1. Kingdom Animalia: Multicellular; no cell walls; chemoheterotrophic.
2. Kingdom Plantae: Multicellular; cellulose cell walls; usually photoautotrophic.
3. Kingdom Fungi: Chemoheterotrophic; unicellular or multicellular; cell walls of
chitin; develop from spores or hyphal fragments.
4. Kingdom Protista: A catchall for eukaryotic unicellular and multicellular
organisms that do not fit in other kingdoms.
e. Classification of Viruses.
i. Viral species: Population of viruses with similar characteristics that occupies a particular
ecological niche.
Note: You will not be tested on the rest of the material in Chapter 10.