Question

Question from Campbell Biology Chapter 16:

42) Which of the following represents the order of increasingly higher levels of organization of chromatin?
A) nucleosome, 30-nm chromatin fiber, looped domain
B) looped domain, 30-nm chromatin fiber, nucleosome
C) looped domain, nucleosome, 30-nm chromatin fiber
D) nucleosome, looped domain, 30-nm chromatin fiber
E) 30-nm chromatin fiber, nucleosome, looped domain

Answer 1

The correct order of chromatin organization from least to most complex is: nucleosome, 30-nm chromatin fiber, looped domain. DNA wraps around histones forming nucleosomes, which coil into chromatin fibers and then further arrange into looped domains.

Step-by-step explanation:

The order of increasingly higher levels of organization of chromatin is important to understand the structural complexity of eukaryotic chromosomes. Starting with the most fundamental unit, DNA wraps around histone proteins to form a nucleosome. Several nucleosomes together form a coiled structure known as a 30-nm chromatin fiber, which is a more compact form of the chromatin. Finally, these fibers form looped domains, which are even higher-level structures within the chromosome. Therefore, the correct answer to the question is: A) nucleosome, 30-nm chromatin fiber, looped domain.

Answer 2

B) looped domain, 30-nm chromatin fiber, nucleosome
C) looped domain, nucleosome, 30-nm chromatin fiber