Gel Electrophoresis

Gel Electrophoresis

A technique used to separate DNA fragments (or other macromolecules, such as RNA and proteins) based on their size and charge.

Process of Gel Electrophoresis

Charged molecules respond to the current by moving from the sample wells into the gel; negatively charged molecules move toward the anode, positively charged molecules move toward the cathode.

Staining and Visualization

Gels are stained with ethidium bromide to visualize DNA fragments.

Gel

Made of agarose, it is used for DNA electrophoresis.

Electrophoresis Tank

Holds the gel during electrophoresis.

Comb and Micropipette

Used for loading DNA samples onto the gel.

Power Supply

Maintains constant conditions for electrophoresis.

Buffers

Establish pH and electrical charge.

Electrophoresis Chamber

Holds the gel during electrophoresis.

Electrodes

Provide current for DNA migration.

Gel Caster and Comb

Used for loading DNA samples onto the gel.

How does Electric Current Affect DNA Movement in Gel Electrophoresis?

An electric current pulls DNA molecules, with smaller fragments moving fastest toward the electrode.

Use of Gel Electrophoresis in Criminal Cases

Used to help catch criminals by analyzing DNA fragments.

Use of Gel Electrophoresis in Paternity Tests

Helps determine parentage by comparing DNA fragments.

Role of Restriction Enzymes

Cut DNA at specific recognition sites to create smaller fragments for separation and characterization using gel electrophoresis.

Anode

The positive electrode where oxidation occurs.

Cathode

The negative electrode where reduction occurs.

Purpose of Gel Electrophoresis

To separate molecules (DNA strands and proteins) according to their length.

Function of Power Supply

Produces an electric current in the electrophoresis chamber.

Function of Buffer Solution

Carries the electric current.

Which Electrode is Farther From the Wells?

The Positive electrode.

Which DNA Fragments are Farther From the Wells?

The Smallest fragments.