What role do proteins play in enabling the enormous amount of dna in a eukaryotic cell to fit into the nucleus, and what are those protein called

Histones

Explanation:

Histones are the proteins that are found in the eukaryotic cells. As the size of the eukaryotic nucleus is long it is required to be tightly packed. The histone proteins aid in the packaging of DNA inside the structural units called nucleosomes. These proteins help in maintaining the shape of the chromosome. These act as a spool around the DNA winds and play an important role in gene regulation.

you are certainly talking about this picture:

a: is the label of the white square, it is showing the  replication fork, formed by helicase (d) ==> so it is the site of dna separation and replication 

b: is a new dna brand that is following directly the replication fork, so it is continuous ==> built continuously from 5' to 3

c: dna polymerase cannot replicate dna on its own, it needs the of their proteins, and one of them plays the role of a clamp which fixes  the dna with the dna template and increases  the processivity of the enzyme. ==>   stops polymerase from falling off the  template.

d: is the enzyme responsible for forming the replication fork (helicase) ==> unwinds and separates dna into two strands

e: is the delayed strand, it is built  in the opposite sense of the helicase, so dna will be built in fragments ==> built  fragments from 5' to 3 joins

and finally f: is the enzyme that builds  the new dna strand (dna polymerase) ==>   adds nucleotides to make a new dna helix.

credit: gradman555p98x9p

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