which of the following list structures from smallest to largest?
A. chromosome, supercoil, coil, nucleosome, double helix
B. chromosome, coil, double helix, nucleosome, super coil
C. double helix, nucleosome, coil, super coil, chromosome
D. nucleosome, coil, double helix, chromosome, super coil
double helix, nucleosome, coil, super coil, chromosome
To determine the correct order of the list structures, we need to understand the hierarchical organization of DNA. Here is a breakdown of each structure:
1. Double Helix: This is the basic structure of DNA, consisting of two strands twisted around each other.
2. Nucleosome: DNA wraps around histone proteins to form nucleosomes. Nucleosomes are the repeating units of chromatin, which is the complex of DNA and proteins.
3. Coil: Nucleosomes further coil and pack together, forming a compact structure called a chromatin fiber or chromatin thread.
4. Supercoil: The chromatin fiber continues to coil and fold upon itself, forming a supercoil. Supercoiling is important for compaction and regulation of gene activity.
5. Chromosome: The highest level of DNA packaging is the chromosome. Chromosomes are the structures visible during cell division and contain one long DNA molecule along with various proteins.
Now, let's compare the given options:
A. chromosome, supercoil, coil, nucleosome, double helix
B. chromosome, coil, double helix, nucleosome, super coil
C. double helix, nucleosome, coil, super coil, chromosome
D. nucleosome, coil, double helix, chromosome, super coil
Based on the hierarchical organization described above, we can determine that the correct order is:
C. double helix, nucleosome, coil, super coil, chromosome