The study of the fossil record of past geo- logical periods and of the phylogenetic relationships between ancient and contemporary plant and animal species.

See Palindromic sequence.

A DNA locus whose 5'-to-3' sequence is identical on each DNA strand. The sequence is the same when one strand is read left to right and the other strand is read right to left. Recognition sites of many restriction enzymes are palindromic. See DNA.

Ampicillin-resistant plasmid developed for this laboratory course. (See Plasmid.)

The closee association of two or more dissimilar organisms where the association is harmful to at least one. See Commensalism, Parasitism, Symbiosis.

Organism which can cause disease in another organism.

A derivation of ColE1, one of the first plasmid vectors widely used. (See Plasmid.)

See Polymerase chain reaction.

A diagram mapping the genetic history of a par- ticular family.

Ability of an organism to remain in a particular setting for a period of time after it is introduced.

A substance that kills harmful organisms (for example, an insecticide or fungicide).

See Bacteriophage.

The observable characteristics of an organism, the expression of gene alleles (genotype) as an observable physical or biochemical trait. See Genotype.

A hormone-like substance that is secreted into the environment.

An enzyme that hydrolyzes esters of phosphoric acid, removing a phosphate group.

A bond in which a phosphate group joins adjacent carbons through ester linkages. A condensation reaction between adjacent nucleotides results in a phosphodiester bond between 3' and 5' carbons in DNA and RNA.

A class of lipid molecules in which a phos- phate group is linked to glycerol and two fatty acyl groups. A chief component of biological membranes. (See Inositol phospholipid.)

The addition of a phosphate group to a compound.

A map showing physical locations on a DNA molecule, such as restriction sites, and sequence-tagged sites. (See Mapping.)

See U.S. Department of Agriculture.

See U.S. Department of Agriculture.

A clear spot on a lawn of bacteria or cultured cells where cells have been Iysed by viral infection.

A circular DNA molecule, capable of autonomous replication, which typically carries one or more genes encoding antibiotic resistance proteins. Plasmids can transfer genes between bacteria and are important tools of transformation for genetic engineers. (See Nicked circle, pAMP, Relaxed plasmid, Stringent plasmid, Supercoiled plasmid.)

The effect of a particular gene on several different traits.

A change in a single base pair of a DNA sequence in a gene. (See Mutation.)

Catalyzes the addition of adenine residues to the 3' end of pre-mRNAs to form the poly(A) tail. (See Polymerase.)

Electrophoresis through a matrix composed of a synthetic polymer, used to separate proteins, small DNA, or RNA molecules of up to 1000 nucleotides. Used in DNA sequencing. (See Electrophoresis.)

A mixture of immunoglobulin molecules secreted against a specific antigen, each recognizing a different epitope.

Controlled by or associated with more than one gene.

A short DNA sequence containing several re- striction enzyme recognition sites that is contained in cloning vectors.

A molecule composed of repeated subunits.

Synthesizes a double-stranded DNA molecule using a primer and DNA as a template. (See Poly(A) polymerase, Polymerase chain reaction, RNA polymerase, Taq polymerase.)

A procedure that en- zymatically amplifies a DNA polymerase. (See Polymerase.)

Variant forms of a particular gene that occur simultaneously in a population.

A DNA polymer composed of multiple nucleotides. (See Nucleotide.)

A polymer composed of multiple amino acid units linked by peptide bonds.

A multiple of the haploid chromosome number that results from chromosome replication without nuclear division.

A polymer composed of multiple units of monosaccharide (simple sugar).

A recombinant organism into which has been cloned antigenic determinants from a number of different disease-causing organisms. (See Vaccine.)

A local group of organisms belonging to the same species and capable of interbreeding.

See U.S. Department of Agriculture.

A cell or cell line taken directly from a living organism, which is not immortalized.

A short DNA or RNA fragment annealed to single-stranded DNA, from which DNA polymerase extends a new DNA strand to produce a duplex molecule.

See Proteinaceous infectious particle.

A sequence of DNA or RNA, labeled or marked with a radioactive isotope, used to detect the presence of complementary nucleotide sequences. See Nucleotide.

A bacterial cell lacking a true nucleus; its DNA is usually in one long strand. See Eukaryote.

A region of DNA extending 150-300 bp upstream from the transcription start site that contains binding sites for RNA polymerase and a number of proteins that regulate the rate of transcription of the adjacent gene. (See Constitutive promoter.)

Either of the two haploid gamete nuclei just prior to their fusion in the fertilized ovum.

An enzyme that cleaves peptide bonds that link amino acids in protein molecules.

A polymer of amino acids linked via peptide bonds and which may be composed of two or more polypeptide chains. (See Polypeptide.)