What is meant by the "beads on a string" model of chromatin?
A)The beads are the histones, and the string is the transcriptionally active DNA loops.
B)The beads are the nucleosomes, and the string is the linker DNA.
C)The beads are molecules of DNA polymerase that attach to the DNA string.
D)The beads are ribosomes, and the string is the mRNA that has been transcribed from active chromatin.
E)The beads are the heterochromatic regions that are tightly compacted, and the strings are euchromatic regions that are being actively transcribed.

Question

Quizplus · Accepted Answer

The "beads" in the beads-on-a-string model of chromatin are nucleosomes, which consist of histone proteins wrapped around a segment of DNA. The "string" is the linker DNA that connects the nucleosomes. This model helps to explain how the tightly compacted chromosomes can be highly dynamic and undergo changes in gene expression.

What Is Meant by the "Beads on a String" Model