The main enzyme of replication, whose function is to link together individual nucleotides along a template strand, is called...

• A. Helicase
• B. DNA polymerase
• C. Ligase
• D. Primase

Answer: (B)

The main concept here is DNA synthesis during replication. The enzyme that links together individual nucleotides to form a new strand by reading a template and catalyzing the formation of phosphodiester bonds is DNA polymerase. It adds nucleotides to the 3' end of the growing strand, using the template strand to specify the correct complementary base pairs and building the new DNA in the 5' to 3' direction. Primers, laid down by primase, provide the starting point for synthesis, and the other enzymes have supportive roles: helicase unwinds the double helix, and ligase seals the remaining nicks after fragments are synthesized on the lagging strand. DNA polymerase is the key enzyme that actually builds the new DNA chain by linking nucleotides together.