So 1000 G's basically means the molecules and things inside our test tube experience a gravitational or an acceleration that is 1000 times as high as the gravitational acceleration. Now in the first step, because we're only using 1000 GS, we're going to separate things like the nuclei of the cells. So in the pellet we're going to have the nuclei and above in a supernatin, we're going to have everything else. So once we obtain this test tube, we basically remove the pellet and then we take the supernatin and we expose the supernatin to yet another centrifugation process. But now we bump our acceleration, we increase it to 10,000 GS. Once we do that, we basically form a pellet that now contains our mitochondria, which are smaller than nuclei.