Final answer:
DNA replication begins at the replication origin, a specific DNA sequence recognized by proteins. Helicase unwinds the DNA and replication forks are formed. Replication proceeds bidirectionally from the origin.
Step-by-step explanation:
During DNA replication, the process begins at a specific DNA sequence called the replication origin. The replication origin is recognized by certain proteins that bind to this site. An enzyme called helicase unwinds the DNA, forming Y-shaped structures called replication forks. Two replication forks are formed at the origin, and replication proceeds in both directions.