Polytene chromosomes were first observed by
Batanetzky-$1980$
Heitz and Bauer -$1935$
Balbiani -$1881$
Stevens and Wilson -$1905$
The accessibility of promoter regions of bacterial $DNA$ in many cases regulated by the interaction of proteins with sequences termed
The twenty third pair of chromosomes in man is known as
Who among the following scientists developed cytochemical technique for the presence of $DNA$
Life span of $mRNA$ in E. coli is