Of course, it's more complicated than this, but you get the point. And once we wrap it around, it's now much smaller than before, and now we can fit it easily into the nucleus of our cell. So that is what a chromosome is. It's this entire structure that contains the DNA, as well as the proteins that hold that dense structure together. So the chromosomes are basically the DNA, along with the proteins that are found within the nucleus of our cells and the cells of other organisms. Now, what's the special feature?