Many biological structures are composed of smaller units assembled into more complex structures having functions based on their structural organization. For the following complex structures, describe the smaller units, their assembly into the larger structures, and one major function of these larger, organized structures.

A eukaryotic chromosome

The explanation regarding the  smaller units, their assembly into the larger structures is to be described below:

The following information should be considered:

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The smaller units are histone proteins and DNA (more specifically a single DNA strand). The DNA strand is coiled around these histones into a beads-on-a-string like structure. RNA, non-histone protein, and metallic ions are some other, but less important components. The major function of eukaryotic chromosomes is allowing the essential processes like mitosis and meiosis to occur and transferring DNA in an efficient, well-regulated manner.

the answer is b.) hydrogen bonds between bases.