| The semiconservative nature of DNA replication was established by Meselson and Stahl in their classic experiment with bacteria. They grew bacteria in \[{{N}^{15}}-N{{H}_{4}}Cl\] containing medium, washed and then incubated in fresh medium with |
| \[{{\operatorname{N}}^{14}}\]-containing compounds and allowed to grow for three generations. \[CsCl\] density gradient centrifugation of isolated DNA established the nature of semiconservative DNA replication. The pictorial representation below shows the position of differentially labelled DNA in \[CsCl\] density gradient. |
 |
| Had the DNA replication been conservative, what would have been the pattern? |
A)
B)
C)
D)
Correct Answer: C
Solution :
In the conservative model, the parental DNA molecule directs the synthesis of an entirely new double-stranded DNA molecule, such that after one round of replication, one molecule is conserved as two old strands. This is repeated in the second round. If DNA replication had been conservative, two bands of \[{{N}^{15}}\] and \[{{N}^{14}}\] - DNA will be observed in \[\operatorname{CsCl}\] density gradient.
You need to login to perform this action.
You will be redirected in
3 sec
