Classification and Taxonomy

Binomial Nomenclature

-(Genus species) -The classification method used in the Linnaean system of taxonomy, which assigns each species both a genus name and a specific epithet (ex: Homo sapiens) -First word is capitalized, second word is lowercase -All must be underlined or italicized

Staphylococci

-Clusters of cocci, which look like bunches of grapes -Form when the planes of cell. division are random

What are the different morphologies/shapes for prokaryotic cells?

-Cocci -Coccobacilli -Bacilli -Vibrio -Spirillum -Spirochete -Pleomorphic

Name five arrangements for cocci bacteria.

-Diplococci (pairs) -Streptococci (chains) -Staphylococci (clusters) -Tetrad (fours) -Sarcinae (cuboidal packets-like rubic's cube)

Bacteria

-Domain which includes (along with Archaea) all prokaryotic cells and contain bacterial rRNA sequences.

Archaea

-Domain which includes (along with Bacteria) all prokaryotic cells and contain archaeal rRNA sequences.

Eukarya

-Domain which includes all eukaryotic cells, all of which contain eukaryotic rRNA sequences.

Endospores

-Each vegetative cell transforms into one endospore (not reproductive structure (spore)) -Poor conditions cause it to become an endospore -Can germinate under good conditions and begin to multiply again -Each endospore germinates to form on vegetative cell -Constitute a defensive strategy against hostile or unfavorable conditions -Serious concern to food processors, health care professions, and governments

What are endospores?

-Each vegetative cell transforms into one endospore (not reproductive structure (spore)) -Poor conditions cause it to become an endospore -Can germinate under good conditions and begin to multiply again -Each endospore germinates to form on vegetative cell -Constitute a defensive strategy against hostile or unfavorable conditions -Serious concern to food processors, health care professions, and governments

Prokaryotes

-Most diverse group of organisms -Thrive in all kinds of habitats -Only a few are capable of colonizing humans and causing disease.

Can you name five ways we determine the phylogenetic relationship among bacteria?

-Physical characteristics -Biochemical tests -Serological tests -Phage -Analysis of nucleic acids

How do domains fit into our taxonomic viewpoint and how were organisms placed into each domain?

-Proposal of three domains based on three basic types of cells as determined by ribosomal nucleotide sequence. -Eukarya, Bacteria, and Archaea -Cells in the three domains also differ with respect to many other characteristics.

Domains

-Proposal of three domains based on three basic types of cells as determined by ribosomal nucleotide sequences. -Eukarya, Bacteria, and Archaea -Cells in the three domains also differ with respect to many other characteristics.

Linnaeus

-Provided the system that standardized the naming and classification of organisms based on characteristics they have in common. -Grouped similar organisms that can successfully interbreed into categories call species. -Proposed only two kingdoms.

Spores

-Reproductive cells produced at the end of prokaryotic cell -Each clone can develop into a clone of the original organism.

Dichotomous key

-Series of paired statements worded so that only one of two "either/or" choices applies to any particular organism. -Key directs user to another pair of statements, or provides name of organism.

Name four arrangements for bacilli bacteria.

-Single bacillus (single) -Diplobacilli (plural) -Streptobacilli (chains) -Palisade (oblong/oval stair-steps) -V-shapes

Taxonomy

-The science of classifying and naming organisms Kingdom, Phylum, Class, Order, Family, Genus, Species

rRNA

-ribosomal RNA -Molecules that are present in all cells and are crucial to protein synthesis.

Name and briefly describe the three types of asexual reproduction used by prokaryotes.

1) Binary Fission- Cell replicates its DNA, Cell elongates, Cross wall forms, Daughter cells are produced. 2) Snapping Division- Occurs in some gram + bacteria, Variation of binary fission. 3) Reproductive Structure Formation- Spore formation, Fragmentation, Budding.

Binary Fission

1) Cell replicates its DNA 2) The cytoplasmic membrane elongates, separating DNA molecules 3) Cross wall forms; membrane invaginates 4) cross wall forms completely 5) Daughter cells

What is a dichotomous key?

A dichotomous key is a series of paired statements worded so that only one of two "either/or" choices applies to any particular organism.

How do prokaryotes reproduce?

All prokaryotes reproduce asexually. There are three methods of asexual reproduction. No sexual reproduction.

Budding

An out growth of the original cell (a bud) receives a copy of the genetic material and enlarges. Eventually the bud is cut off from the parental cell, typically while it is still small.

Pleomorphic

Bacteria that vary in size and shape.

How does binary fission affect the arrangement of prokaryotic cells.

Binary fission affects the arrangement of prokaryotic cells by the way in which the planes divide the cells.

Tetrad

Cocci divided in two planes.

Sarcinae

Cocci divided into three planes to form cuboidal packets (like rubic's cube)

Diplococci

Cocci that remain attached in pairs.

What are the three domains?

Eukarya, Bacteria, and Archaea.

Spirochete

Flexible spirals (thin)

Coccibacilli

Intermediate to cocci/bacilli

Can you name all the parts to the Linnaeus classification scheme?

Kingdom, Phylum, Class, Order, Family, Genus, Species.

What did Linnaeus contribute to taxonomy?

Linnaeus provided the system that standardized the naming and classification of organisms based on characteristics they have in common. He grouped similar organisms that can successfully interbreed into categories called species. Binomial Nomenclature (Genus species). He proposed only two kingdoms.

Streptococci

Long chains of cocci.

Fragmentation

Process by which small motile filaments glide away from the parental strand.

What two genera produce endospores?

Produced by Gram+ Bacillus and Clostridium

Eubacteria

Prokaryotic cells. Known as "true bacteria."

Bacilli

Rod shaped

Cocci

Roughly spherical

Vibrio

Slightly curved rods

Gram Negative Bacteria

Stains pink

Gram Positive Bacteria

Stains purple

Spirillum

Stiff spirals (thick)

Why is taxonomy important?

Taxonomy enables scientists to both organize large amounts of information about organisms and make predictions based on knowledge of similar organisms.

Bacillus

gram+ bacteria which produce endospores (central endospores)

Clostridium

gram+ bacteria which produce endospores (subterminal endospores)