DNA Isolation (Onion)

Ice-Cold Ethanol

The main reacting reagent used for the isolation of DNA from onion is the 2x volume __________

Cloudy White Layer

After adding 2x volume ice-cold ethanol to the onion, the first result to form is the ___________ at the boundary between the aqueous layer and the ethanol

Thin Threads or Clumps

After adding 2x volume ice-cold ethanol to the onion, the second result to form is the __________, which appears and start to float upward into the ethanol phase

Whitish to Translucent, Jelly-Like with Precipitate

After adding 2x volume ice-cold ethanol to the onion and placing it in the watch glass, the isolated DNA will appear as __________

Lysis of Onion Cells

The mincing and mashing that physically break the cell walls and membranes to expose the cells to the homogenizing solution is a property of the principle __________

Lysis Buffer

In standard onion-DNA protocols, the _______ (HS) contains Detergent and Salt

Detergent

The _______ dissolves membrane phospholipids and proteins, which causes the cells and nuclei to lyse and release DNA

Salt (NaCl or Similar)

The _________ shields the negatively charged phosphate groups on DNA, which helps keep proteins dissolved and later promotes DNA Precipitation

Role of Warming (50Cº)

The __________ helps the detergent act more effectively in disrupting membranes and denaturing proteins

50-60º

At _________, many DNases (enzymes that cut DNA) begin to lose activity, allowing the DNA itself to remain stable for short exposures

Enzymatic Degradation

The heating under the principle of Role of Warming helps protect the DNA from _________, which is a biological process where enzymes catalyze the breakdown of complex substances, such as polymers, pollutants, and other organic materials, into smaller, less harmful molecules.

Cooling in an Ice Bath

The rapid _________ prevents overheating and further DNA damage

Precipitation

The cooling of DNA slows residual enzyme activity and prepares the sample for ________ by stabilizing the DNA in solution

Filtration Through Cotton

The __________ is the principle for removing the large cellulose cell-wall fragments and tissue debris, which consist of the filtrate such as soluble DNA, proteins, and other cell components in the HS

True

DNA is highly polar and soluble in water, but insoluble in cold ethanol, especially when salt is present

True or False

Dielectric Constant

The principle of Precipitation with 2x Volume of Ice-Cold 95% Ethanol lowers the _________ of the solution, and together with salt, neutralizes charge repulsion between DNA strands

Ice-Cold Ethanol

In _________, Nucleic Acids form visible, white, stringy filaments, which rises to the ethanol layer and can be spooled onto a glass rod