Agarose Gel Techniques in Molecular Biology

The video tutorial explains the use of agarose gels in molecular biology for DNA separation. It covers the preparation of agarose gels with different concentrations, the process of heating and cooling the gel, and the safe use of ethidium bromide for DNA staining. The tutorial also provides detailed instructions on setting and pouring the gel, ensuring no bubbles form, and the importance of safety precautions throughout the process.

What is the primary purpose of using agarose gels in molecular biology?

• To separate and purify nucleic acid fragments

• To measure the pH of solutions

• To amplify DNA sequences

• To synthesize proteins

How does the size of DNA fragments affect their movement through an agarose gel?

• Smaller fragments move faster

• Smaller fragments move slower

• Larger fragments move faster

• Size does not affect movement

What concentration of agarose is typically used for separating large DNA fragments?

• 2%

• 0.4%

• 3%

• 0.1%

What is the role of the running buffer in agarose gel preparation?

• To cool the gel

• To increase the gel's transparency

• To stain the DNA

• To dissolve the agarose powder

Why is it important to heat the agarose mixture in intervals?

• To avoid the formation of bubbles

• To allow the mixture to solidify

• To ensure the mixture remains cold

• To prevent the mixture from boiling over

What temperature should the agarose gel be cooled to before adding dye?

• 50-60°C

• 90-100°C

• 70-80°C

• 20-30°C

What safety precaution is necessary when handling ethidium bromide?

• Work in a dark room

• Wear double gloves

• Use a plastic apron

• Use a face mask

What is the purpose of using tape on the gel tray?

• To prevent the gel from drying

• To ensure the gel sets evenly

• To mark the gel's boundaries

• To stop the liquid gel from leaking

Why is it important to pour the gel slowly into the tray?

• To ensure the gel is evenly colored

• To allow the gel to cool gradually

• To avoid creating bubbles and splashes

• To prevent the gel from solidifying too quickly

What indicates that the gel is fully set and ready for use?

• It becomes warm to the touch

• It changes from transparent to opaque

• It changes from opaque to transparent

• It becomes transparent