The cells are given back to the patient after treatment. Phage A virus for which the natural host is a bacterial cell. Phenotype Observable characteristics of an organism produced by the organism's genotype interacting with the environment. Physical map Map where the distance between markers is the actual distance, such as the number of base pairs. Plasmid Autonomously replicating, extrachromosomal circular DNA molecules, distinct from the normal bacterial genome and nonessential for cell survival under nonselective conditions.
Some plasmids are capable of integrating into the host genome.
A number of artificially constructed plasmids are used as cloning vectors. Pleiotropy The phenomenon of variable phenotypes for a number of distinct and seemingly unrelated phenotypic effects. Compare single-gene disorders. Polymerase Any enzyme that catalyzes the formation of DNA or RNA from deoxyribonucleotides or ribonucleotides. Because the newly synthesized DNA strands can subsequently serve as additional templates for the same primer sequences, successive rounds of primer annealing, strand elongation, and dissociation produce rapid and highly specific amplification of the desired sequence.