THE MOLECULAR BASIS OF INHERITANCE
DNA REPLICATION
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
Addition of new nucleotides to the leading strand
|
|
|
Addition of new nucleotide to the lagging strand
|
|
|
Formation of a phosphodiester bond between the 3’-OH of one Okazaki fragment and the 5’-phosphate of the next on the lagging strand
|
|
|
Base pairing of the template and the newly formed DNA strand
|
Detailed explanation-1: -The reaction catalyzed by DNA ligase. This enzyme seals a broken phosphodiester bond. As shown, DNA ligase uses a molecule of ATP to activate the 5′ end at the nick (step 1) before forming the new bond (step 2).
Detailed explanation-2: -DNA ligases catalyse the formation of a phosphodiester bond between adjacent 3′ hydroxyl and 5′ phosphate terminal groups in double stranded DNA.
Detailed explanation-3: -DNA ligases catalyze the formation of phosphodiester bonds between juxtaposed 5’ phosphate and a 3’-hydroxyl terminus in duplex DNA. This activity can repair single-stranded nicks in duplex DNA and join duplex DNA restriction fragments having either blunt ends or homologous cohesive ends.
Detailed explanation-4: -DNA polymerase catalyzes the formation of the phosphodiester bond by adding the deoxynucleoside triphosphate onto the growing polynucleotide chain. During this step-wise process, a single pyrophosphate molecule is released every time the chain is elongated by one deoxyribonucleotide.