The acetyl-CoA pathway is a pathway of autotrophic CO_{2 fi}xation widespread in obligate anaerobes including methanogens, homoacetogens and sulfate-reducing bacteria

Bacteriohodopsin is a membrane protein containing retinal produced certain extreme halophiles and capable of light-mediated proton motive force formation

A compatible solute is an organic or inorganic substance accumulated in the cytoplasm of a halophilic organism that maintains osmotic pressure

They contain both hyperthermophile and cold-dwelling organisms

This phylum contains primarily methanogens, the extreme halophiles, thermoplasma and some marine hyperthermophiles

A halorhodopsin is a light-driven chloride pump that accumulates Cl^- within the cytoplasm

Phytanyl is a branched-chain hydrocarbon containing 20 carbon atoms and commonly found in the lipids of archaea

Reverse DNA gyrase is a protein universally present in hyperthermophiles that introduces positive supercoils into circular DNA

A solfatara is a hot, sulfur-rich, generally acidic environment commonly inhabited by hyperthermophilic archaea

Thermosome is a heat-shock protein complex that functions to refold partially heat-denatured proteins in hyperthermophiles

Amoeboid movement is a type of motility in which cytoplasmic streaming via pseudopodia moves the organism forward

A basal organism is an organism or group of organisms which evoles early and gives rise to other groups

Chitin is a polymer of N-acetylglucosamine commonly found in the cell walls of fungi

A ciliate organism is a protist characterized in part by rapid motility driven by numerous short appendages called cilia

Coenocytic is the presence of multiple nuclei in fungal hyphae without septa

A colonial organism is the growth form of certain protists and green algae in which several cells live together and cooperate for feeding, motility or reproduction; an early form of multicellularity

Conidia are asexual spores of fungi

A hydrogenosome is an organelle of endosymbiotic origin present in certain anaerobic eukaryotic microorganisms that functions to oxidize pyruvate to H₂, CO₂, acetate and one molecule of ATP

Intermediate filament is a filamentous polymer fo fibrous keratin proteins supercoiled into thicker fibers that functions in maintaining cell shape and the positioning of certain organelles in the eukaryotic cell

Microfilament is a filamentous polymer of the protein actin that helps maintain the shape of a eukaryotic cell

A mushroom is a the above-ground fruiting body (or basidiocarp) of basidiomycete fungi

A peroxisome is an organelle that functions to rid the cell of toxic substances such as peroxides, alcohols and fatty acids

A slime mold is a nonphototrophic protist that lacks cell walls and that aggregates to form fruiting structures (cellular slime molds) or masses of protoplasm (acellular slime molds)

The stroma is the inner membrane surrounding the lumen of the chloroplast

The thylakoid is a membrane layer containing the photosynthetic pigments in chloroplasts