Decoding DNA: The Science Behind Sequencing Techniques

DNA sequencing involves determining the order of bases in a DNA strand. The process starts with cutting DNA into smaller pieces, inserting them into plasmids, and multiplying them in bacterial cells. The DNA is then isolated and prepared for sequencing by adding various ingredients, including terminator bases. Through a series of heating and cooling cycles, DNA polymerase synthesizes new strands until a terminator base is added, stopping the process. The resulting fragments are separated by length using electrophoresis, and a laser detects the fluorescent tags on terminator bases. The sequence is read by converting the colors into letters, revealing the DNA sequence.

What is the first step in DNA sequencing?

• Adding terminator bases

• Heating the DNA to 96°C

• Using electrophoresis

• Inserting DNA into plasmid DNA

What is added to the isolated DNA to start the sequencing reaction?

• Free DNA bases and terminator bases

• Only plasmid DNA

• Only DNA polymerase

• Only DNA primers

At what temperature do DNA primers bind to plasmid DNA?

• 37°C

• 60°C

• 50°C

• 96°C

What causes the DNA polymerase to stop adding bases?

• The temperature is too high

• The DNA polymerase runs out of bases

• A terminator base is added

• The DNA strand is too long

How are DNA fragments separated by length?

• Through electrophoresis

• By adding more DNA polymerase

• By heating and cooling

• Using a centrifuge

What role does the capillary tube play in electrophoresis?

• It heats the DNA

• It binds DNA primers

• It adds terminator bases

• It applies an electrical charge

What happens to the DNA fragments as they move through the gel?

• They are heated to 96°C

• They are arranged by size

• They are converted into proteins

• They are mixed with plasmid DNA

How are terminator bases detected at the end of the capillary?

• By adding more DNA polymerase

• Through a chemical reaction

• Using a laser and camera

• By a microscope

What color does the terminator base 'A' fluoresce?

• Green

• Yellow

• Blue

• Red

What is the final step in determining the DNA sequence?

• Heating the DNA to 96°C

• Using a centrifuge

• Converting colors into letters

• Adding more terminator bases