Select the $correct$ match :
Francois Jacob and Jacques Monod -$ Lac\,operon$
Alec Jeffreys -$Streptococcus\,pneumoniae$
Matthew Meselson and F. Stahl -$Pisum sativum$
Alfred Hershey and Martha Chase -$TMV$
Gene regulation governing lactose operon of E.coli that involves the lac $I$ gene product is
Repressor protein is formed from
$A$ : Lac operon exerts negative control only.
$R$ : The operator is occupied by aporepressor during regulation
'Operon model' for gene regulation in bacteria was proposed by
An environmental agent that triggers transcription from an operon is a: