BSC 220 DNA Extraction

DNA Extraction: What is used to collect and rinse worms?

Collection/wash buffer.

DNA Extraction: Why are worms rinsed?

To remove bacterial food and contaminants.

DNA Extraction: What happens if rinsing is skipped?

Bacterial DNA and proteins may contaminate the sample.

DNA Extraction: What releases DNA from cells?

Lysis buffer.

DNA Extraction: What does detergent do?

Disrupts cell membranes.

DNA Extraction: What happens without effective lysis?

DNA remains trapped inside cells.

DNA Extraction: What does proteinase K do?

Digests proteins, including many nucleases.

DNA Extraction: What happens if proteinase K is omitted?

Protein contamination and incomplete DNA release may increase.

DNA Extraction: Why incubate during protein digestion?

To support digestion and sample breakdown.

DNA Extraction: What happens if digestion time is insufficient?

Incomplete digestion can lower DNA yield.

DNA Extraction: What does Tris do?

Maintains a suitable pH.

DNA Extraction: What happens if Tris is omitted?

pH control may be reduced.

DNA Extraction: What does EDTA do?

Binds metal ions required by many nucleases.

DNA Extraction: What happens if EDTA is omitted?

Protection against metal-dependent nucleases is reduced.

DNA Extraction: What does RNase remove?

RNA.

DNA Extraction: What happens if required RNase treatment is omitted?

RNA can contaminate the DNA preparation.

DNA Extraction: Why clarify the lysate before column loading?

To remove insoluble debris.

DNA Extraction: What happens if required clarification is skipped?

Debris may clog the column.

DNA Extraction: What establishes DNA-binding conditions?

Binding buffer and any required alcohol.

DNA Extraction: What does ethanol help do during binding?

Promotes DNA attachment to silica.

DNA Extraction: What captures DNA in a spin column?

The silica membrane.

DNA Extraction: What happens if binding reagents are omitted?

DNA may escape into the flowthrough.

DNA Extraction: What does wash buffer remove?

Salts, proteins, and other contaminants.

DNA Extraction: What happens if washing is skipped?

Contaminants remain and may inhibit PCR.

DNA Extraction: What happens if required ethanol is missing from wash buffer?

DNA may be lost or poorly purified.

DNA Extraction: Why dry-spin the column?

To remove residual ethanol-containing wash solution.

DNA Extraction: What happens if the dry spin is skipped?

Ethanol may inhibit downstream enzymes.

DNA Extraction: What is used to elute DNA?

Low-salt elution buffer or suitable nuclease-free water.

DNA Extraction: Where is DNA after elution?

In the collected liquid, called the eluate.

DNA Extraction: What happens if elution is skipped?

DNA remains attached to the membrane.