Final answer:
Incomplete cellular homogenization leads to unbroken cells that are found in the second supernatant.
Step-by-step explanation:
Cellular homogenization is often incomplete, and the mixture has unbroken cells. These cells are found in the second supernatant. Supernatant is the liquid portion of a mixture that remains after centrifugation, while unbroken cells form a pellet. In cell fractionation, after the cell debris is pelleted, the DNA-containing supernatant is transferred to a clean tube.