Question

__________________________ attaches the first nucleotide to the OH group at the three end of the preceding Okazaki fragment and then continues in the 5 to 3 direction along the nucleotide strain removing and replacing one at a time the RNA nucleotides of the primer

Answer 1

DNA polymerase I attaches the first nucleotide to the 3' end of the preceding Okazaki fragment and replaces RNA nucleotides with deoxynucleotides during DNA replication.

Step-by-step explanation:

The enzyme that attaches the first nucleotide to the OH group at the 3' end of the preceding Okazaki fragment and continues in the 5' to 3' direction along the nucleotide strand, removing and replacing one at a time the RNA nucleotides of the primer, is called DNA polymerase I.

DNA polymerase I binds to the 5' end of the primer and adds dNMPs to the 3' end of the newer Okazaki fragment as it hydrolyzes NMPs from the previous Okazaki fragment in the 5' to 3' direction.

After the RNA nucleotides are removed, DNA polymerase I catalyzes their replacement with the appropriate deoxynucleotides. Finally, DNA ligase stitches together the Okazaki fragments by forming phosphodiester bonds between the 3'-OH end of one fragment and the 5' phosphate end of the other fragment.