Question

Choose the correct statement if the screening is carried out by screening by expression in vivo.

(a) The proportion of recombinants carrying gene of interest is small

(b) The recombinants carrying gene of interest don’t complement the host mutation

(c) Mutation should be affecting many genes

(d) Most of the products selected would be result of complementation

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Answer 1

Right choice is (a) The proportion of recombinants carrying gene of interest is small

Easiest explanation: The proportion of recombinants carrying the gene of interest is small. The host is mutant towards the gene of interest and thus the recombinants complement the host mutation. Mutation used should affect only one gene. The most of the products selected would be a result of reversion of only mutation and not complementation.