Gel Electrophoresis and DNA Fingerprinting Answer questions about gel electrophoresis below. 1. How does the process of gel electrophoresis separate DNA fragments? 2. Why is the fact that DNA has a negative charge so important in the gel electrophoresis process? Practice interpreting DNA fingerprints using the gel provided below. 3. Measure the distance traveled in centimeters by each band in the DNA standard known sizes (DNA ladder) of Lane 1, then the sample fragments in Lane 2. Record the results in the tables following. To do this, measure (in cm) from the bottom of the well (the blue box at the top of the gel) to the bottom of each DNA band (the dark boxes) 1 2 3 4 5 6 7 Fragment Fragment B Fragment LABORATORY 17 Gel Electrophoresis and DNA Fingerprinting
3 Fragment Molecular Weight (kb) 1 10 2 8 4 2 5 15 6 125 7 1 8 0.75 9 0.5 10 0.25 Distance Travelled (cm) DEC Plot the distance traveled on the x-axis and the molecular weight on the y-axis of the graph You can either Use MS Excel to create a log graph with a best-fit line or trendline. Please print your log graph and attach to the lab review sheet. Watch this video if you need help. https://youtu.be/_S75X4FsCOA O, use the log graph below and a ruler to manually create a best- fit line. (For an example of best-fit line graph, see Figure 10.3, p. 124) Distance and molecular weight of DNA fragments Did you Plotal data points? Use a ruler to draw an angled in that This line will be used to imale sue of unknown DNA Molecular weight loss Distance b e lom) LABORATORY 17 Gel Electrophoresis and DNA Fingerprinting
We were unable to transcribe this image
17/ Practice Creating and Interpreting DNA Fingerprints 7. Refer to the sample DNA restriction creme fragment table in Lab 16 Review Sheet (p. 219). The fragments are listed largest to smallest. You are not plotting the entire pieces of DNA with restriction cut sites, merely the fragments after they have been digested. Use your knowledge of DNA electrophoresis and the restriction enzyme fragment size data to recre- ate a visual representation of the DNA fingerprint resulting from the use of each restriction enzyme. To align DNA fragments across each type of enzyme, it may be useful to write the size of each fragment above its band in the gel. EcoRI Hindi BamHI Nool 230 LABORATORY 17 Gel Electrophoresis and DNA Fingerprinting
8. How many DNA fragments resulted from the use of Hindi? 9. Based on the number of DNA fragments produced by HindIII, how many restriction sites were there? through the gel matrix than 10. The larger fragments move (faster or slower) the smaller fragments. electrode. 11. The smaller fragments move closer to the (positive or negative)
Gel Electrophoresis and DNA Fingerprinting Answer questions about gel electrophoresis below. 1. How does the process of gel electrophoresis separate DNA fragments? 2. Why is the fact that DNA has a negative charge so important in the gel electrophoresis process? Practice interpreting DNA fingerprints using the gel provided below. 3. Measure the distance traveled in centimeters by each band in the DNA standard known sizes (DNA ladder) of Lane 1, then the sample fragments in Lane 2. Record the results in the tables following. To do this, measure (in cm) from the bottom of the well (the blue box at the top of the gel) to the bottom of each DNA band (the dark boxes) 1 2 3 4 5 6 7 Fragment Fragment B Fragment LABORATORY 17 Gel Electrophoresis and DNA Fingerprinting
3 Fragment Molecular Weight (kb) 1 10 2 8 4 2 5 15 6 125 7 1 8 0.75 9 0.5 10 0.25 Distance Travelled (cm) DEC Plot the distance traveled on the x-axis and the molecular weight on the y-axis of the graph You can either Use MS Excel to create a log graph with a best-fit line or trendline. Please print your log graph and attach to the lab review sheet. Watch this video if you need help. https://youtu.be/_S75X4FsCOA O, use the log graph below and a ruler to manually create a best- fit line. (For an example of best-fit line graph, see Figure 10.3, p. 124) Distance and molecular weight of DNA fragments Did you Plotal data points? Use a ruler to draw an angled in that This line will be used to imale sue of unknown DNA Molecular weight loss Distance b e lom) LABORATORY 17 Gel Electrophoresis and DNA Fingerprinting
17/ Practice Creating and Interpreting DNA Fingerprints 7. Refer to the sample DNA restriction creme fragment table in Lab 16 Review Sheet (p. 219). The fragments are listed largest to smallest. You are not plotting the entire pieces of DNA with restriction cut sites, merely the fragments after they have been digested. Use your knowledge of DNA electrophoresis and the restriction enzyme fragment size data to recre- ate a visual representation of the DNA fingerprint resulting from the use of each restriction enzyme. To align DNA fragments across each type of enzyme, it may be useful to write the size of each fragment above its band in the gel. EcoRI Hindi BamHI Nool 230 LABORATORY 17 Gel Electrophoresis and DNA Fingerprinting
8. How many DNA fragments resulted from the use of Hindi? 9. Based on the number of DNA fragments produced by HindIII, how many restriction sites were there? through the gel matrix than 10. The larger fragments move (faster or slower) the smaller fragments. electrode. 11. The smaller fragments move closer to the (positive or negative)
Answer
1. Answer- gel electrophoresis is a process
used in the lab to separate the DNA molecules or any charged
molecule according to their size.
An electric charge is applied to the gel and the one end of the
gel has a positive charge and the other end has a negative
charge.
As the DNA molecules are negatively charged when the current is
applied to the gel DNA molecules moves toward the positively
charged end of the gel.
The negatively charged end of the gel consists of some wells.
When the gel runs the shorter pieces of DNA travel through the
wells of the gel matrix faster than the longer DNA pieces. As a
result, the shorter DNA pieces are close to the positively charged
end and the longer pieces remain near to the wells of the matrix.
That is how the DNA fragments are separated in the process of gel
electrophoresis.
