BIOL 1208 Fall 2022
Molecular Biology II In-Class Assignment
Name: Riley Howell
Lab Partner Name(s): John Jardine
Remember: Although you work with partners for lab experiments, assignments must be completed independently. All
text must be able to be processed in Turnitin, so do not use screenshots. See the syllabus for more information.
AGAROSE GEL ELECTROPHORESIS AND RESULTS ANALYSIS
1. Complete Table 11-1; be sure to include a complete caption. Show your calculations.
Table 11-1. Predicted Phenotypes and Number of Restriction Fragments and Size of Base Pairs from
three different plasmids.
Number of EcoRI Size(s) of EcoRI Restriction Predicted Bacterial
Plasmid
Restriction Fragments Fragments (bp) Phenotype(s)
Tetracycline Resistance,
pBR322 1 4,359bp
Ampicillin Resistance
Tetracycline Resistance,
pDR1453 2 4957bp, 8002bp
UV Resistance
pGPS1.1 1 4,791bp Tetracycline Resistance
One Strand: Total Size (4,359bp) = Single Strand Size (4,359bp)
Two Strands: Total Size (12,959bp) – Given Strand Size (4,957bp) = Other Strand Size (8,002bp)
One Strand: Total Size (4,791bp) = Single Strand Size (4,791bp)
2. What is a DNA ladder and what is its purpose in this lab?
A DNA Ladder is a line that acts as a weighted marker to determine DNA fragment size by displaying
numbers that are the fragment sizes in the base pairs. In this lab, a DNA Ladder is used to determine the
number of fragments and their sizes in the base pairs of each sample.
3. Determine the number and approximate size of each of the fragments from the bacteriophage λ ladder from the
physical map (Figure 11-11). Show your calculations and include units. (the textbook says to assume HindIII is
making the cuts, therefore I assumed cuts were at these HindIII sites)
Number: 7 cuts, 8 fragments
Sizes (kb): 48.5kb (total size) – 44 kb (approx. end fragment size) = 4.5kb, 44kb (end fragment size) – 38kb
(approx. fragment size) = 6kb, 38kb (approx. fragment size) – 37.5kb (approx. fragment size) = 0.5kb, 37.5kb
(approx. fragment size) – 37kb (approx. fragment size) = 0.5kb, 37kb (approx. fragment size) – 27.5 (approx.
fragment size) = 9.5kb, 27.5kb (approx. fragment size) – 25kb (approx. fragment size) = 2.5kb, 25kb (approx.
fragment size) – 23.5kb (approx. fragment size) = 1.5kb, 48.5kb (total fragment size) – 25kb (sum of all
calculated fragment sizes) = 23.5kb
48.5kb fragments in order: 23.5kb, 1.5 kb, 2.5kb, 9.5kb, 0.5kb, 0.5kb, 6kb, 4.5kb
4. Provide a picture or a clear sketch of your gel results (desired image height: 2.5-4 inches). Label the approximate
fragment sizes with units for the λ ladder and each plasmid sample.
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Molecular Biology II In-Class Assignment
Name: Riley Howell
Lab Partner Name(s): John Jardine
Remember: Although you work with partners for lab experiments, assignments must be completed independently. All
text must be able to be processed in Turnitin, so do not use screenshots. See the syllabus for more information.
AGAROSE GEL ELECTROPHORESIS AND RESULTS ANALYSIS
1. Complete Table 11-1; be sure to include a complete caption. Show your calculations.
Table 11-1. Predicted Phenotypes and Number of Restriction Fragments and Size of Base Pairs from
three different plasmids.
Number of EcoRI Size(s) of EcoRI Restriction Predicted Bacterial
Plasmid
Restriction Fragments Fragments (bp) Phenotype(s)
Tetracycline Resistance,
pBR322 1 4,359bp
Ampicillin Resistance
Tetracycline Resistance,
pDR1453 2 4957bp, 8002bp
UV Resistance
pGPS1.1 1 4,791bp Tetracycline Resistance
One Strand: Total Size (4,359bp) = Single Strand Size (4,359bp)
Two Strands: Total Size (12,959bp) – Given Strand Size (4,957bp) = Other Strand Size (8,002bp)
One Strand: Total Size (4,791bp) = Single Strand Size (4,791bp)
2. What is a DNA ladder and what is its purpose in this lab?
A DNA Ladder is a line that acts as a weighted marker to determine DNA fragment size by displaying
numbers that are the fragment sizes in the base pairs. In this lab, a DNA Ladder is used to determine the
number of fragments and their sizes in the base pairs of each sample.
3. Determine the number and approximate size of each of the fragments from the bacteriophage λ ladder from the
physical map (Figure 11-11). Show your calculations and include units. (the textbook says to assume HindIII is
making the cuts, therefore I assumed cuts were at these HindIII sites)
Number: 7 cuts, 8 fragments
Sizes (kb): 48.5kb (total size) – 44 kb (approx. end fragment size) = 4.5kb, 44kb (end fragment size) – 38kb
(approx. fragment size) = 6kb, 38kb (approx. fragment size) – 37.5kb (approx. fragment size) = 0.5kb, 37.5kb
(approx. fragment size) – 37kb (approx. fragment size) = 0.5kb, 37kb (approx. fragment size) – 27.5 (approx.
fragment size) = 9.5kb, 27.5kb (approx. fragment size) – 25kb (approx. fragment size) = 2.5kb, 25kb (approx.
fragment size) – 23.5kb (approx. fragment size) = 1.5kb, 48.5kb (total fragment size) – 25kb (sum of all
calculated fragment sizes) = 23.5kb
48.5kb fragments in order: 23.5kb, 1.5 kb, 2.5kb, 9.5kb, 0.5kb, 0.5kb, 6kb, 4.5kb
4. Provide a picture or a clear sketch of your gel results (desired image height: 2.5-4 inches). Label the approximate
fragment sizes with units for the λ ladder and each plasmid sample.
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