Question

You’ve been asked to prepare the gel. How much agarose would you need to weigh in order to prepare 50 ml of 2% gel? Show your math.

List three things to which one needs to pay special attention when loading a gel for DNA electrophoresis.

What would be the volume of the PCR sample you would have loaded in live lab?

The loading buffer has a dual purpose. Explain.

There are multiple reasons for loading a DNA ladder (size standard) in the gel with your samples. State two.

What was the color of the positive pole electrode in the virtual gel box?

What voltage would you use if you ran DNA gel electrophoresis?

How would your results be affected – if at all – if the voltage was half the strength, and you ran the gel for the

     amount of time specified in the protocol?

How would your results be affected – if at all – if the voltage was twice the strength, and you ran the gel for the

     amount of time specified in the protocol?

Answer 1

1) this showing weight/ volume ratio

1% means we have to add 1gm of agarose in 100ml of buffer.

But we have to make 2% in 50 ml

So 1% of 50 ml will be 0.5 gm

And 2% will be 1 gm

To make 50ml of 2% buffer we have to add 1gm of agarose.

2) during loading a gel thing should be considered

- buffer ionic connections

- percentage of gen dependent on size of seprated DNA

- concentration of ETBR

3) 5ul of 20ul PCR reaction is enough to load on the gel.

4) loading buffer has various comopnent

One of the comopnent is glycerol, this make sample heavy so it will easily sink in to well.

Second it contain xylenecyanol which is used as a tracking dye to track the electrophoresis.

Please post questions separately