Gel Electrophoresis

Electrophoresis

migration of charged particles in an electrical field

Electrophoresis separates molecules according to

charge, size and shape

The electrophoresis gel is made of

agarose

During electrophoresis, molecules with a net negative charge move towards the

positive electrode

The positive electrode is called

anode

What is a buffer?

substance that remove H+ or OH- ions from a solution and prevent the pH from changing

What is an acid?

An acid is a source of hydrogen ions, H⁺. pH less than 7.

What is a base?

A substance that produces hydroxide ions (OH-) in solution. pH greater than 7

What are electrodes?

Two metal strips which connect to electrical current to a wire.

What color is the cathode (electrons enter the box)?

black

What color is the anode (electrons leave the box)?

red

What is the cell potential? How is it measured?

The cell potential is the electrical energy difference between electrodes and is measured in volts.

How is electrical current measured?

milliamperes

What are the parts of a gel electrophoresis box

gel box, gel chamber, comb, dams, gel block, electrodes, power source

Where was the purple color produced in the Electrophoresis Exploration?What gas is produced?

cathode; hydrogen gas

Where was the red color produced in the Electrophoresis Exploration? What gas was produced?

anode; oxygen gas

What is required for electrons to flow between the anode and cathode?

ions

Why is the gel submerged in buffer?

The buffer maintains the pH of the system and ensures the gel does not overheat.

What is the purpose of the gel block?

holds the agarose gel

What is the purpose of the electrophoresis chamber?

holds gel and buffer

What is the purpose of the comb and dams?

allows you to make the gel with sample wells

What is the purpose of electrodes?

connects the chamber and power source

How do you identify unknowns using a gel?

compare the distance and direction of each sample with a known sample or control

What did we use to identify pH changes in the Electrophoresis Exploration Lab?

Universal Indicator

What is the charge of the cathode?

negative