Atom, cell, tissue, organ
Answer:
A parasite is an organism that lives within or on a host. The host is another organism. The parasite uses the host's resources to fuel its life cycle. It uses the host's resources to maintain itself.
Explanation:
DNA unwinding begins at the Origin of replication.
In sub-atomic science, DNA replication is the natural procedure of creating two indistinguishable copies of DNA from one unique DNA particle. This procedure happens in every single living creature and is the reason for natural legacy.