DNA and RNA gels

Question 1

Genomic DNA Isolation method

Answer 1

• Mash it up
• Lyse the cells (lysis), put cells in buffer, then EDTA (CHELATING AGENT that inhibits nucleases) and a detergent which dissolves membranes
• Remove proteins (add NaCl)
• Precipitate DNA (use ethanol)

Question 2

How to quantify DNA and RNA with a SEPCTROPHOTOMETER

Answer 2

For pure solutions, use a spectrophotometer to measure UV radiation absorbed by the bases.

Use a solvent to suspend the nucleic acids and place samples in a quartz cuvette

‘Zero’ reading required to blank the spectrophotometer with a sample of solvent

Beer lambert equation used to characterise substances, check purity, tell the wavelength of light absorbed, based off their absorbance.

Question 3

Beer lambert equation

Answer 3

Question 4

Quantification of DNA and RNA with flourescence and intercalated dyes

Answer 4

Measure UV-induced light emission of fluorescence from intercalated dyes, useful when not enough DNA to quantify with spectrophoto

Question 5

What does gel electrophoresis let us do

Answer 5

• See size of DNA / RNA fragments
• Purity of these samples
• Condition of the samples, degradation

(charge is used to draw the sample through the gel, distance travelled by sample depends on charge and size, DNA is negatively harged and runs towards anode, circular forms of DNA migrate in agarose differently from linear DNAs of same mass, for RNA a formaldehyde is used as a denaturing agent)

Question 6

How to make agarose gel for gel electrophoresis

Answer 6

UNDERSTAND HOW GEL ELECTROPHORESIS WORKS

Question 7

Additional factors effecting mobility of DNA fragments in agarose gels

Answer 7

Question 8

When is DNA acrylamide gel used

Answer 8