Lambda phage true ist:

Ans. (a) Transduction Transmission of genetic material = gene transfer = acquisition of characteristic occur by four process. a. Transformation: - Transfer of genetic information (about 10-50 genes) through the free DNA. Seen mainly in pneumococci; bacillus species and Hemophilus influenza. Any characteristic may be transferred by transformation. b. Transduction: - Transfer of poion of DNA from one to other bacteria by agency of bacteriophage (acts only as vehicle). It may be generalised (when it involves any segment of donor DNA) or restricted (when specific bacteriophage transduces only a paicular genetic trait). It is most widespread mechanism of gene transfer among prokaryotes. Episomes and plasmids (e.g. plasmid determining Pn resistance in staphylococci) may also transduced. It is used in genetic engineering in the treatment of some inborn errors of metabolism. c. Conjugation Bacterial equivalent of sexual mating Described by Lederberg and Tatum in strain of E. coli (K12), e.g. Transfer of episomes and plasmids of drug resistance. d. Lysogenic conversion: - Phage DNA becomes integrated with bacterial chromosome as the prophage which codes for new characteristic, e.g. toxin production in C. diptheriae.