Final answer:
The enzyme responsible for adding nucleotides to the growing DNA chain during DNA replication is DNA polymerase, which includes different types such as DNA pol I, II, and III, with DNA pol III being the main enzyme for synthesis and pol I being important for primer removal and replacement.
Step-by-step explanation:
The Enzyme Involved in DNA Replication
The correct answer to the question is DNA polymerase. This enzyme is responsible for adding nucleotides to the growing DNA strand that are complementary to the template strand during the process of DNA replication. Three main types of DNA polymerase are known in prokaryotes: DNA pol I, DNA pol II, and DNA pol III, with DNA pol III being the principal enzyme required for DNA synthesis. DNA polymerase I also plays a role in the process by removing RNA primer nucleotides from Okazaki fragments and replacing them with the appropriate deoxynucleotides.
DNA polymerases are crucial for the replication process because they can only add nucleotides to a pre-existing strand of nucleic acid, usually provided by a primer, and because they are involved in proofreading and error correction during replication to ensure fidelity. It is the addition of nucleotides by DNA polymerase that requires energy obtained from the nucleotides themselves as they provide the energy for the formation of the phosphodiester bonds between incoming nucleotides and the growing chain.