DNA Isolation and Extraction Techniques

These flashcards cover key concepts related to the isolation and extraction of DNA and RNA, as described in the lecture notes.

Why do we isolate nucleic acids?

To diagnose infections, diseases, for oncology, paternity testing, as well as for research, agriculture, environment, and forensic analysis.

What is lysis in the context of nucleic acid extraction?

The process of breaking the cell wall and membrane to release nucleic acids for analysis.

What is the ideal condition for isolating nucleic acids?

Nucleic acids should be free of contamination from proteins, carbohydrates, lipids, and other nucleic acids.

What is a common method for degrading cell walls in bacteria or fungi?

Mechanical grinding, mixing, or using enzyme products that digest cell walls.

What is the purpose of a centrifuge in DNA extraction?

To separate components based on density, allowing for the collection of white blood cells containing DNA.

What component is used to precipitate proteins during DNA extraction?

Ammonium acetate, which is added to a solution containing proteins to separate them from DNA.

What is the purpose of isopropanol in DNA extraction?

To precipitate DNA from solution after it has been isolated.

How is the purity of extracted DNA assessed?

By measuring the A260/A280 ratio, with pure DNA ideally around 1.8 to 2.0.

What is the purpose of RNase-free areas in RNA extraction?

To prevent contamination that could degrade the fragile RNA.

What does Reverse Transcriptase PCR accomplish?

It converts RNA into complementary DNA (cDNA) before conducting PCR, allowing the analysis of RNA expression and detecting RNA viruses.

What is the significance of Taq polymerase in PCR?

It is a thermostable enzyme used for DNA amplification, allowing the PCR process to endure high temperatures.

What does the amplification program in PCR consist of?

A series of cycles including denaturation, annealing, and extension to amplify the target DNA.

What is the difference between qualitative and quantitative PCR?

Qualitative PCR detects the presence of DNA, while quantitative PCR measures the amount of DNA produced during the reaction.

What is Gel electrophoresis used for?

To assess the quality and size of DNA fragments.

What is the main risk associated with PCR?

Contamination, leading to false results or amplification of non-target sequences.