Final answer:
DNA polymerases require a template strand, add nucleotides to the 3' end, and can only add to a pre-existing strand of nucleic acid.
Step-by-step explanation:
In DNA replication, there are three observations that have been made for all DNA polymerases:
- All DNA polymerases require a template strand to synthesize a new complementary strand.
- They grow new DNA by adding nucleotides to the 3' end of the growing DNA chain through condensation reactions.
- All DNA polymerases can only add to a pre-existing strand of nucleic acid.
DNA polymerases play a crucial role in DNA replication by ensuring the accurate and efficient synthesis of new DNA strands.