Question

Fill in the following table to explain the effects of the following mutations on the growth of bacteriophage lambda. Label the mutation as either cis-or trans-acting; dominant or recessive if the wild-type allele is supplied in trans; whether it forms clear, turbid or no plaques on E. coli at 30°C or 42°C; and whether it forms turbid or no plaques on an E. coli lysogen at 30°C | dominant/ l plaque at l plaque at 1 Plaque on λ | cis/ Mutation recessive | 30°C 42°C | lysogen at 30°C cl (non-functional) PRE-defective ORI OL (a double mutant doesn't bind CI clI ts (30°C,42 C) cII* rotease insensitive

Answer 1

Mutation
cI- (non-functional)	Trans	Dominant	Yes	No	Yes (clear)
Pre – defective	Cis	Recessive	Yes	No	Yes (turbid
Ori Oli(a double Mutant does not bind CI)	Cis	Recessive	No	yes	Yes (None)
CII ts	Trans	Dominant	yes	No	Yes
CII (protease insensitive)	Trans	Dominant	Yes	No	Yes