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Vocab 23 and 24
Microorganisms
| Term | Definition |
|---|---|
| Halophile | An organism that can grow in, or favors environments that have very high salt concentrations |
| Bacillus | A rod-shaped bacterium |
| Coccus | A sphere-shaped bacterium |
| Spirillum | A spiral-shaped bacterium |
| Streptococcus | A coccus that grows with others in chains; examples include cocci of the disease-causing species (streptococcus mutans |
| Virulent | Describes a microorganism that causes disease and that is highly infectious; strictly, refers only to viruses that reproduce by the lytic cycle |
| Oncogene | A gene that induces cancer, or uncontrolled cell proliferation |
| Viroid | An infectious agent that is made up of a short, circular, singe strand of RNA that does not have a capsid; the smallest known particle that is able to replicate |
| Prion | An infectious particle that consists only of a protein and that does not contain DNA or RNA |
| Virus | A nonliving, infectious particle composed of a nucleic acid and a protein coat; it can invade and destroy a cell |
| Envelope | A membranelike layer that covers the capsids of some viruses |
| Retrovirus | A virus that contains single-stranded RNA and produces a reverse transcriptase, which converts RNA to DNA |
| Bacteriophage | A virus that infects bacteria |
| Lytic Cycle | A method of viral replication that results in the destruction of a host cell and the release of many new virus particles |
| Virulent Cycle | virulent and lytic can be used almost interchangeably |
| Lysogenic Cycle | A method of viral replication in which a viral genome is replicated as a pro-virus without destroying the host cell |
| Temperate Virus | A virus whose replication includes the lysogenic cycle |
| Prophage | The viral genome (DNA) of a bacteriophage that has entered a bacterial cell, has become attached to the bacterial chromosome, and is replicated with the host bacterium's DNA |
| Inactivated Virus | an inactivated vaccine consists of virus particles, bacteria, or other pathogens which are grown in culture and then killed using a method such as heat or formaldehyde |
| Attenuated Virus | Attenuation takes an infectious agent and alters it so that it becomes harmless or less virulent. These vaccines contrast to those produced by killing the virus |
| Vector | In biology, any agent, such as a plasmid or a virus, that can incorporate foreign DNA and transfer that DNA from one organism to another; an intermediate host that transfers a pathogen or a parasite to another organism |
| Antibiotic | A substance that inhibits the growth of or kills microorganisms |
| Conjugation | In algae and fungi, an exchange of genetic material that occurs between two temporarily joined cells; in prokaryotes, the process by which organisms bind together and one cell transfers DNA to the other cell through a structure called a sex pilus |
| Obligate Anaerobe | An organism that needs the absence of oxygen in order to live |
| Facultative Anaerobe | An organism that can live with or without oxygen |
| Exotoxin | A potent, extracellular toxin secreted by some gram positive |
| Endotoxin | A toxin that occurs in the outer membrane of Gram negative bacteria and that is released when the bacterial cell breaks apart |
| Antibiotic Resistance | The ability of a population of bacteria to survive the lethal effects of an antibiotic |
| Pathology | A scientific study of disease |