What is chromatin composed of?

Chromatin is primarily composed of double helix DNA that is wrapped around histone proteins. This structure is crucial for the organization of DNA within the nucleus of eukaryotic cells. The combination of DNA and histones forms nucleosomes, which are the fundamental units of chromatin. These nucleosomes coil and fold to create higher-order structures, allowing the long DNA molecules to fit into the cell nucleus while also playing significant roles in gene regulation and expression.

The presence of histones is essential in this context, as they help stabilize the DNA's structure and contribute to the regulation of gene accessibility. When chromatin is in a more compact form, such as during cell division, it further protects the DNA and ensures proper segregation.

In contrast, other options do not accurately describe the composition of chromatin. Single-stranded RNA, for instance, is not a component of chromatin, nor are ribosomes. The term "loose DNA that is not compacted" lacks specificity regarding the crucial role of histones and does not represent the structured form in which DNA exists in the cell. Thus, the most accurate description of chromatin is the double helix DNA wrapped around histone proteins.