Final answer:
The DNA is held onto the histone core by ionic interactions and hydrogen bonds. This allows the DNA to be tightly packed and organized around the histones, forming nucleosomes. This packaging helps to regulate gene expression and ensure the proper organization of the DNA within the nucleus.
Step-by-step explanation:
The DNA is held onto the histone core by ionic interactions. Histones are positively charged proteins that bind to the negatively charged phosphate backbone of DNA. This interaction is primarily due to the attraction between the positive charges on the histones and the negative charges on the DNA.
Additionally, there are hydrogen bonds between the histones and the DNA bases, which further stabilize the interaction. The combination of these ionic and hydrogen bonds allows the DNA to be tightly packed and organized around the histones.
The DNA wraps around an octamer of histones, forming structures called nucleosomes. The nucleosomes, which look like beads on a string, are linked together by linker DNA. This packaging helps to regulate gene expression and ensure the proper organization of the DNA within the nucleus.