Read the following statements.
(i) Primers used in PCR are small chemically synthesised oligosaccharides.
(ii) E. coli is closely related to Salmonella.
(iii) There are 3 basic steps in genetically modifying an organism.
(iv) The techniques of the genetic engineering overcome the limitation of traditional hybridisation procedures
In these statements how many are correct?
Escherichia coli
Escherichia coli is closely related to Salmonella and hence the plasmid from the Salmonella can be used to form recombinant DNA and transferred to Escherichia coli for cloning.
Three basic steps in genetically modifying an organism
The three basic steps in genetically modifying an organism are as follows:-
Traditional hybridisation
Traditional hybridisation procedures like the desired crosses often led to the inclusion and multiplication of undesirable genes along with the desired genes in the progenies. This limitation can be overcome by the techniques of genetic engineering.
Therefore the given statements ii, iii and iv are correct.
Final answer
(b) 3