<prompt> Direct uptake of free DNA by bacterial cell isTranslationTranscriptionTransformationConjugation  <response>: Ans. c Transformation Ref. Anantanarayan, Microbiology, 6th ed., 53; Ref. Q. 101 of MH-2005Method of transmissionCommentTransformation A phenomenon in which transfer of genetic information occurs through the agency of free DNA. Certain cell lines, such as cancer cells, are also able to grow indefinitely in culture by this mechanism.Transduction Transfer of a portion of DNA from one bacteria to another by bacteriophage. It is not confined to transfer of chromosomal DNA; it transduces episomes and plasmids also. Bacteriophages are viruses that parasitise bacteria and consist of nucleic acid core and a protein coat. It is excellent tool for genetic mapping of bacteria.Lysogenic conversion Phage DNA becomes integrated with bacterial chromosome as prophage, which multiplies synchronously with host DNA and is transferred to daughter cells; this is lysogeny and bacteria harbouring prophages are lysogenic bacteria. In transduction, phage acts only as vehicle carrying bacterial genes from one cell to another, but in lysogenic conversion, phage DNA itself is new genetic element.Conjugation The process whereby male or donor bacteria mates or makes physical contact with female or recipient bacteria and transfers genetic element into it.Sexduction Process of transfer of host genes through f factor, resembles transductionTransfection Transfer of a gene into a cell, enabling the transfected cell to form a new gene product. 