one strand of DNA could be as long as a football field if it were stretched out lengthwise. One of the factors allowing DNA to fit inside the nucleus of a cell is its ability to:
A. break apart into separate genes
B. extend to form very long, thick molecules
C. coil tightly around associated proteins
D. denature form the effect of an enzyme
C. Coil tightly around associated proteins
Coil tightly around associated proteins
The correct answer is C. coil tightly around associated proteins.
DNA is a long and thin molecule that carries genetic information in cells. In order to fit inside the nucleus of a cell, which is a relatively small compartment, the DNA molecule needs to be compacted. This is achieved by coiling the DNA molecule tightly around associated proteins called histones, forming a structure known as chromatin.
Chromatin is a complex of DNA and proteins that condenses and compacts the DNA molecule, allowing a large amount of DNA to be stored in a small space. The DNA wraps around histone proteins, forming a series of nucleosomes, which are like "beads on a string". These nucleosomes further coil and fold upon themselves, creating a compact and organized structure.
This coiling and folding of DNA helps it to occupy less space in the nucleus. When the cell needs to access certain genes for transcription and protein synthesis, the DNA can temporarily uncoil and unwind in specific regions, allowing the required genes to be exposed and "read" by the cellular machinery.
So, one of the factors allowing DNA to fit inside the nucleus of a cell is its ability to coil tightly around associated proteins.