Answer:
linker DNA
Explanation:
the classic beads on a string structure is termed as the nucleosome; which is the most basic level of chromosome packaging. the nucleosome is made up of 2 molecules each of the four histone proteins (H2A, H2B, H3, H4) to form an octamer around which a length of DNA is wrapped. linkage of this nucleosome to another nucleosome is done by a length of linker DNA and a linker histone (H1). thus experimentally to produce this structure, the linker DNA between two nucleosomes is degraded by nucleases to extract the structure. thus the linker DNA is not retained after the experiment.