Final answer:
The β dimer, part of the DNA polymerase holoenzyme, increases DNA synthesis processivity and requires γδ subunits for its assembly and removal around DNA.
Step-by-step explanation:
The student's question is related to the structure and function of the DNA replication machinery, specifically the role of the sliding clamp, known as the β dimer, and how it relates to the DNA polymerase holoenzyme. The β dimer is ring-shaped which encircles DNA and allows the DNA polymerase to maintain a strong association with the template, making the holoenzyme highly processive. This means that once the DNA polymerase is bound to DNA, it can synthesize a long stretch of DNA without dissociating. As for the assembly or removal of the β dimer, it requires the action of clamp loader proteins, specifically the subunits γδ. These subunits are responsible for opening and closing the β dimer ring so it can load onto the DNA and be removed when necessary. This process is crucial for the function of DNA polymerases during DNA replication.