James Watson: Glossary
Bacteriophage: viruses that infect bacteria, also
known as just "phage". Geneticists studied phage replication in viruses
as a method of studying genes.
Chargaff's Rule: a pattern in the amounts of the
four bases: adenine, guanine, cytosine, and thymine (A=T, and G=C) found
in DNA. The discovery of this relationship was made by Erwin Chargaff
and was instrumental to Watson and Crick's discovery of the structure
chemotherapy: The treatment of disease by means of chemicals that
have a specific toxic effect upon the disease producing microorganisms
(antibiotics) or that selectively destroy cancerous tissue (anticancer
chromosomes: The self-replicating genetic structures of cells containing
the cellular DNA that bears in its proteins.
codon: term coined by molecular geneticist Sydney Brenner meaning
a triplet of bases that specifies an amino acid, the building blocks of
DNA (deoxyribonucleic acid): a molecule consisting of two intertwining
chains that form a double helix and composed of the sugar deoxyribose,
phosphoric acid, and a sequence of four bases (adenine, guanine, cytosine,
thymine). DNA is found in the nucleus of the cell and is the chemical
basis of heredity.
eugenics: The scientific study of artificial selection towards
desirable characteristics. It evolved into a controversial movement devoted
to improving the human species through the control of hereditary factors
genome: The total set of genes carried by an individual or cell.
heterogeneous: Composed of varied cell types.
interferon: A family of proteins derived from human cells which
normally has a role in fighting viral infections by preventing virus multiplication
messenger RNA (mRNA)- the strand of nucleotides that "carry" genetic
information from the DNA in the cell's nucleus, to the cytoplasm where
protein synthesis takes place.
the mutual exclusion principle- a phenomenon
demonstrated in 1941 by Max
Delbrück and Salvador
Luria, that only one type of bacterial virus, or phage, infected a
virus at one time, to the exclusion of another type of phage.
nucleic acids: found in the cells of all living organisms,
nucleic acids are composed of sugars, phosphates, and nitrogenous bases.
DNA and RNA are nucleic acids.
oncogene: a mutated and/or over-expressed version of a normal
gene of animal cells that in a dominant fashion can release the cell from
normal restraints on growth and thus alone or in concert with other changes,
convert a cell into a tumor cell.
pathogenicity: The ability of a parasite to inflict damage on the
recombinant DNA: Spliced DNA formed from two or more different
sources that have been cleaved by restriction enzymes and joined by ligases,
enzymes that catalyze the joining process.
ribosome: a cellular structure that exists either singly or in
clusters (polysomes) outside the nucleus, and is the site of protein synthesis.
RNA (ribonucleic acid): a nucleic acid that participates in protein
synthesis; similar in structure to DNA except its sugar is ribose and
it contains uracil instead of thymine.
transduction: The transfer of a gene from one bacterium to another
by a bacteriophage. In generalized transduction any gene may be transferred
as a result of accidental incorporation during phage packaging. In specialized
transduction only specific genes can be transferred, as a result of improper
recombination out of the host chromosome of the prophage of a lysogenic
transfer RNA (tRNA): adaptor molecules that carry amino acids to
the ribosomes, the site of protein synthesis in a cell. tRNA recognizes
the three-letter nucleic acid code, thus "decodes" the sequence so the
proper amino acids are attached for protein synthesis.
Certain technical terms referenced from:
British Telecommunications "The On-Line Medical Dictionary"
15 Dec. 2000