When I started to study microbiology I mainly kept with the basics. I told everyone about bacteria and gave them a short introduction into the study of bacteria. This time, while learning a lot about microbiology in my school and extra-curricula stuff, I learned about the amazing “packaging” of DNA.
A DNA strand, when unpacked, can stretch to about five feet, 10 inches. How, then, does that DNA strand fit into inside a nucleus, inside a cell, inside the body? How can the nearly six feet of DNA fit into a cell that is .00023622 inches in diameter? God has solved the problem.
When a strand of DNA is inside a nuclear envelope inside the cell, it is coiled up in the double helix we all know. But, when the cell begins mitosis or meiosis, the DNA starts to undergo a dramatic change.
Proteins, called histones, connect themselves to the DNA. Seven more histones join the first one and form a circle where the DNA can be completely wrapped around. When the six-foot DNA strand is wrapped around the many histones it begins to arrange itself into a pattern, as can be seen on the picture to the right (histones are green and DNA is blue).
Once the DNA and histones wrap up in this way, the cell uses another protein that does a similar job as the histone did. But, this protein is bigger and wraps up the histone-wrapped DNA itself. This compress the length of the DNA even more.
When the other protein has done its job it then starts to wrap around into a spiral. The spiral then gets so compressed that the chromatin can be distinguished. Next comes the chromosome itself.
Well, there you have it, the wonderful life of packaging DNA. First we have the histones, then the other protein and then spiraling compression, the chromatin and then the chromosome. It may all seem simple but this genius requires a Maker! I have no idea how someone cannot see that.
All in all, the amazing packaging of DNA cause the DNA strand to shrink by 40,000 times!