Question

En (2 points) You isolated your mitochondrial DNA in Part I. In step 6, you discard the supernatant, but keep the pellet. In step 15, you discard the pellet, but keep the supernatant. Explain why the pattern is different between the two steps and the consequence of mixing up these two steps.

Answer 1

Here we are isolating mitochondrial DNA from cheek cells. So for this we have taken 1.5 ml of swirled saline solution in micro centrifuge tube in swirled saline solution, cheek cells are there which is actual source of mitochondria DNA. So in step 5 this centrifuge tube is centrifuged which led to formation of pellet of cheek cells and clear solution.

Do that us why in step 6 supernatant is discarded and pellet is proceed in next step as this pellet is source of mitochondrial DNA.

After the above step , pellet is dissolved in lysis buffer . Lysis buffer lyse the cells and release the DNA ik to supernatant. That's what in step 16 after centrifugation, supernatant is collected as it contains mitochondrial DNA and lysed cells are discarded.

If we discard cell pellets at step 5 it will lead to loss of cells which contain mitchondrial DNA . If in step 1y we discard supernatant, then it will also lead to loss of mitochondrial DNA.