Suppose we have a test tube and inside that test tube we have a bunch of cells. Now, we take those cells and we grind those cells down so that we break the cell membrane and we basically expose all the components, structures and biological molecules found inside the cell. So now we have a homogeneous mixture that consists of all these different types of things like the cell, nucleus, eye, mitochondria and other organelles, ribosomes, proteins and so forth, mixed in into our test tube. Now, if we take the test tube and we place it inside a centrifuge, a process known as centrifugation takes place. And centrifugation is this process by which we use angular motion. We basically accelerate our test tube to very high rotational speeds.