0.5 Glossary  (Page 6/18)

F

• F ^– (recipient) cell E. coli cell lacking the F plasmid and thus incapable of forming a conjugation pilus but capable of receiving the F plasmid during conjugation
• F pilus (F pili) specialized type of pilus that aids in DNA transfer between cells; conjugation pilus of E. coli
• F plasmid (fertility factor) bacterial plasmid in E. coli containing genes encoding the ability to conjugate, including genes encoding the formation of the conjugation pilus
• F’ plasmid integrated F plasmid imprecisely excised from the chromosome; carries with it some chromosomal DNA adjacent to the integration site
• F ⁺ (donor) cell E. coli cell containing the F plasmid, capable of forming a conjugation pilus
• Fab region arm of an antibody molecule that includes an antigen-binding site
• facultative anaerobe organism that grows better in the presence of oxygen but can proliferate in its absence
• false negative negative result to a test for an infection or condition (e.g., presence of antigen, antibody, or nucleic acid) when the infection or condition is actually present
• false positive positive result to a test for an infection or condition (e.g., presence of antigen, antibody, or nucleic acid) when the infection or condition is actually absent
• fastidious organism organism that has extensive growth requirements
• fatty acid lipid that contains long-chain hydrocarbons terminated with a carboxylic acid functional group
• fatty acid methyl ester (FAME) analysis technique in which the microbe’s fatty acids are extracted, converted to volatile methyl esters, and analyzed by gas chromatography, yielding chromatograms that may be compared to reference data for identification purposes
• Fc region region on the trunk of an antibody molecule involved in complement activation and opsonization
• feedback inhibition mechanism of regulating metabolic pathway whereby the product of a metabolic pathway noncompetitively binds to an enzyme early on in the pathway, temporarily preventing the synthesis of the product
• fermentation process that uses an organic molecule as a final electron acceptor to regenerate NAD ⁺ from NADH such that glycolysis can continue
• fever system-wide sign of inflammation that raises the body temperature and stimulates the immune response
• fifth disease a highly contagious illness, more commonly affecting children, marked by a distinctive “slapped-cheek” rash and caused by parvovirus B19
• fimbriae filamentous appendages found by the hundreds on some bacterial cells; they aid adherence to host cells
• fine focusing knob a knob on a microscope that produces relatively small movements to adjust focus
• fixation the process by which cells are killed and attached to a slide
• flagella long, rigid, spiral structures used by prokaryotic cells for motility in aqueous environments; composed of a filament made of flagellin, a hook, and motor (basal body) that are attached to the cell envelope
• flagella staining a staining protocol that uses a mordant to coat the flagella with stain until they are thick enough to be seen
• flagellum (eukaryotic) (plural: flagella) long, whip-like, filamentous external structure found on some eukaryotic cells; composed of microtubules in a 9+2 arrangement; used for locomotion
• flavin adenine dinucleotide (FAD/FADH ₂ ) oxidized/reduced forms of an electron carrier in cells
• flocculant visible aggregation that forms between a substance in suspension (e.g., lipid in water) and antibodies against the substance
• flow cytometry technique analyzing cells for fluorescence intensity; specific subsets of cells are usually labeled in some way prior to the analysis
• fluconazole antifungal drug of the imidazole class that is administered orally or intravenously for the treatment of several types of systemic yeast infections
• fluid mosaic model refers to the ability of membrane components to move fluidly within the plane of the membrane, as well as the mosaic-like composition of the components
• flukes any of the parasitic nonsegmented flatworms (trematodes) that have an oral sucker and sometimes a second ventral sucker; they attach to the inner walls of intestines, lungs, large blood vessels, or the liver in human hosts
• fluorescence microscope a microscope that uses natural fluorochromes or fluorescent stains to increase contrast
• fluorescence-activated cell sorter (FACS) technique for using a flow cytometer to physically separate cells into two populations based on fluorescence intensity
• fluorescent antibody (FA) techniques suite of assays that use a fluorescently labeled antibody to bind to and so make an antigen easy to visualize
• fluorescent enzyme immunoassay (FEIA) EIA in which the substrate is a fluorogen that becomes fluorescent following reaction with the enzyme
• fluorescent the ability of certain materials to absorb energy and then immediately release that energy in the form of light
• fluorochromes chromophores that fluoresce (absorb and then emit light)
• fluorogen nonfluorescent molecule that becomes fluorescent on enzyme or laser activation
• fluorophore molecule that fluoresces when excited by light
• fluoroquinolones class of synthetic antimicrobials that inhibit the activity of DNA gyrase, preventing DNA replication
• focal infection infection in which the pathogen causes infection in one location that then spreads to a secondary location
• focal length the distance from the lens to the image point when the object is at a definite distance from the lens (this is also the distance to the focal point)
• focal point a property of the lens; the image point when light entering the lens is parallel (i.e., the object is an infinite distance from the lens)
• foliose lichens lichens that have lobes that may appear to resemble leaves
• folliculitis a skin infection characterized by localized inflammation of hair follicles, typically producing an itchy red rash
• fomite inanimate item that may harbor microbes and aid in disease transmission
• foodborne disease disease that is transmitted through contaminated food
• fragmentation newly formed cells split away from the parent filament in actinomycetes and cyanobacteria
• frameshift mutation mutation resulting from either an insertion or a deletion in a number of nucleotides that, if not a multiple of three, changes every amino acid after the mutation
• free ribosome eukaryotic 80S ribosome found in the cytoplasm; synthesizes water-soluble proteins
• frequency the rate of vibration for a light wave or other electromagnetic wave
• fruticose lichens lichens that are generally branched with a rounded appearance
• functional groups specific groups of atoms that may occur within a molecule, conferring specific chemical properties
• fungi (singular: fungus) any of various unicellular or multicellular eukaryotic organisms, typically having cell walls made out of chitin and lacking photosynthetic pigments, vascular tissues, and organs
• fungicide chemical or physical treatment that kills fungi
• fungistatic having the ability to inhibit fungal growth, generally by means of chemical or physical treatment
• furuncle a small, purulent skin lesion; sometimes called a boil
• fusion inhibitor antiviral drug that blocks the fusion of HIV receptors to the coreceptors required for virus entry into the cell, specifically, chemokine receptor type 5