Final answer:
Histones are nucleoproteins that play a critical role in the packaging of DNA within the cell, facilitating the organization of DNA into nucleosomes and more compact structures like chromosomes, important for efficient gene regulation and cell division.
Step-by-step explanation:
Histones are indeed considered to be nucleoproteins. This is because they are basic proteins that contain a high proportion of positive amino acids, such as arginine and lysine, which enable them to bind to the acidic, negatively charged DNA strand. In the cell nucleus, DNA is wrapped tightly around the histone octamer to form a complex known as a nucleosome.
These nucleosomes are then linked together by linker DNA, resembling 'beads on a string'. This structure is further compacted into a 30 nm fiber, and ultimately into chromosomes, especially during the metaphase stage of cell division where they reach a width of approximately 700 nm. During interphase, eukaryotic chromosomes show two distinct regions after staining—heterochromatin and euchromatin—based on how tightly the DNA is packaged. Histones are crucial for the folding and packaging of DNA into these compact structures within the cell, effectively controlling access to the genetic material and ensuring efficient organization and segregation during cell division.