A density gradient is produced by centrifuging a solution of caesium chloride (CsCl) at a very high speed, a concentration gradient is set up with CsCl density greater towards the bottom of the tube. How will the three macromolecules - DNA, protein and RNA distribute in this density gradient?

On centrifugation, macromolecules present in the CsCl solution will form bands at distinct point in the gradient. Position of band formation depends on the buoyant density. DNA has a buoyant density of about 1.7 g/ cm3, whereas protein molecules have a much lower buoyant densities and so float at the top of the tube whereas RNA forms a pellet at the bottom.