| A | B |
|---|
| Endospores | A thick-coated, resistant cell produced within a bacterial cell exposed to harsh conditions |
| Antibiotics | A chemical that kills bacteria or inhibits their growth |
| Photoautotrophs | An organism that harnesses light energy to drive to the synthesis of organic compounds from carbon dioxide |
| Chemoautotrophs | An organism that needs only carbon dioxide as a carbon source but that obtains energy by oxidizing inorganic substances |
| Photoheterotrophs | A organism that uses light to generate ATP but that must obtain carbon in organic form |
| Chemoheterotrophs | An organism that must consume organic molecules for both energy and carbon |
| Saprobes | An organism that acts as a decomposer by absorbing nutrients from dead organic matter |
| Parasites | An organism that absorbs nutrients from the body fluids of living hosts |
| Nitrogen fixation | The assimilation of atmospheric nitrogen by certain prokaryotes into nitrogenous compounds that can be directly used by plants |
| Obligate aerobes | An organism that requires oxygen for cellular respiration and cannot live without it |
| Facultative anaerobes | A organism that makes ATP by anaerobic respiration if oxygen is present but that switches to fermentation under anaerobic conditions |
| Obligate anaerobes | An organism that cannot use oxygen and is poisoned by it |
| Anaerobic respiration | When inorganic molecules other than O2 accept electrons at the "downhill" end of electron transport chains |
| Bacteriorhodopsin | A pigment that captures light energy |
| Cyanobacteria | Photosynthetic, oxygen-producing bacteria (formerly known as blue-green algae) |
| domain | taxonomic category above the kingdom level; the three domains are Archaea, Bacteria, and Eukarya |
| domain Archaea | one of the two prokaryotic domains |
| domain bacteria | one of the two prokaryotic domain, the other domain being Archaea |
| peptidoglycan | type of polymer in bacterial cell walls consisting of modified sugars cross-linked by short polypeptides |
| gram stain | staining method that distinguishes between two different kinds of bacterial cell walls |
| gram-positive | describing the group of bacteria with a cell wall that us structurally less complex and contains more peptidoglycan than that of gram-negative. This bacteria is less toxic than gram-negative type |
| gram-negative | describing the group of bacteria that is structurally more complex and contains less peptidoglycan than that of positive-gram. Are usually more toxic than positive-gram |
| capsule | sticky layer that surrounds the cell walls of some prokaryotes, protecting the cell surface and sometimes helping to glue the cell to surfaces |
| pilus, pili | surface appendage in certain bacteria that functions in adherence and the transfer of DNA during conjugation |
| taxis | movement toward or away from a stimulus |
| nucleoid region | region in a prokaryotic cell consisting of a concentrated mass of DNA |
| binary fission | type of cell division by which prokaryotes reproduce; each dividing daughter cell receives a copy of the single parental chromosome |
| transformation | phenomenon in which external DNA is assimilated by a cell |
| conjugation | transfer of DNA between two cells that are temporarily joined in bacteria |
| transduction | DNA transfer process in which phages carry bacterial genes from one host cell to another |
| methanogens | bacteria that obtain energy by oxidizing hydrogen molecules with CO2 and produce methane. |
| extreme halophiles | bacterium that lives in extremely salty environments |
| extreme thermophiles | bacterium that lives in extremely hot environment |
| decomposers | organisms that breakdown corpses, waste, dead vegetation, nitrogen and other elements. |
| symbiosis | ecological relationships between organisms of different species that are in direct contact. |
| symbionts | organisms in a symbiotic relationship |
| host | a larger symbiont in a symbiotic relationship |
| mutualism | both symbionts benefit |
| commensalism | one symbiont receives benefits while leaving a neutral effect on the other. |
| parasitism | a symbiont known as a parasite benefits at the expense of the host |
| parasite | symbiont that benefits at the expense of a hst |
| Koch's postulates | medical guidelines for for medical microbiology |
| exotoxins | proteins excreted by prokaryotes that cause disease symptoms |
| endotoxins | components of the outer membranes of certain gram-negative bacteria that cause health problems to host |
| signature sequences | taxon-specific base sequences at comparable locations in ribosomal RNA or other nucleic acids |
| bacteria | one of two prokaryotic domains, the other is archaea |
| archaea | one of two prokaryotic domains, the other is bacteria |
