Question

Chromatin is said to adopt a "beads on a string" character. The beads represent the _____ and the string is the _____.

		nucleosome core particle; histone tail
		histone octamer; histone tail
		nucleosome core particle; linker DNA
		histone octamer; linker DNA
		linker histone; histone tail

Answer 1

Answer -

Chromatin is said to adopt a "beads on a string" character. The beads represent the nucleosome core particle and the string is the linker DNA. (option 3)

Histones are a special group of proteins found in the nuclei of eukaryotic cells responsible for DNA folding and chromatin formation. Eukaryotic chromatin structure consists of repeating units, known as nucleosomes, which resemble beads on a string connected by sequences of linker DNA.

Nucleosome core particles are observed when chromatin in interphase is treated to cause the chromatin to unfold partially. The resulting image, via an electron microscope, is "beads on a string". The string is the DNA, while each bead in the nucleosome is a core particle. The nucleosome core particle is composed of DNA and histone proteins.