Bio - M11 Prokaryotes

Archaea

Domain of unicellular prokaryotes that have cell walls that do not contain peptidoglycan

Archaea and Eukarya

Domains that share most recent common ancestor

Eukarya

Domain of all organisms whose cells have nuclei, including protists, plants, fungi, and animals

Bacteria

Domain of unicellular prokaryotes that have cell walls containing peptidoglycan

Prokaryotes

Single-celled organisms without a nucleus.

Autotroph

Organisms that make their own food

Chemosynthesis

Process in which chemical energy (H2, S, NH4) is used to produce carbohydrates

Heterotroph

Organism that obtains energy from other organisms

Sapotrophic

Decomposers, type of heterotroph

Pathogen

A disease causing agent

Obligate anaerobe

can't survive in O2

Facultative anaerobe

can live with or without oxygen

Obligate aerobe

need oxygen

Carl Woese

American biologist, pioneered use of 16S rRNA to understand evolutionary history. Discovered Archaea

Coccus

A spherical bacterium.

Bacillus

Rod shaped bacteria

Spirella

spiral, helical shaped bacteria

Gram-negative

Thin peptidoglycan layer under cell membrane. More resistant to antibiotics

Gram-positive

Stains violet. Thick layer of peptidoglycan

Flagella

A long, whip-like filament

Binary fission

Asexual reproduction in single-celled organisms where a cell reproduces by duplicating double-stranded DNA and dividing into two genetically identical daughter cells

Conjugation

In bacteria, the direct transfer of DNA between two cells that are temporarily joined.

Endospore

A thick-walled protective spore that forms inside a bacterial cell and resists harsh conditions.

Biofilm

Colonies of prokaryotes that group together and adhere to environmental surfaces.

Stromatolite

Oldest known fossils formed from many layers of biofilm (bacteria) and calcium carbonate sediment in shallow water

Halophile

salt loving

Thermophilic

heat loving

Acidophilic

acid loving

Methanogen

Archaea that release CH4 as metabolic by-product

Chemosynthetic

Produce food by chemical reactions (H2 + CO2 -> CH4)

Cyanobacteria

Bacteria that can carry out photosynthesis (photoautotrophs)

Photoautotroph

organism that uses energy from sunlight to convert carbon dioxide and water to carbon compounds

Nitrogen fixation

Process of converting N2 (g) into usable form (ammonium NH4+ or nitrate NO3-)

Anabaena

freshwater, photosynthetic, nitrogen-fixing cyanobacteria