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11: PCR and Electrophoresis

Students extract DNA, perform initial and nested PCR amplification of the GAPDH gene, run gel electrophoresis to separate DNA fragments, and interpret band patterns.

DNA Gel Migration Problem

Click to show DNA Gel Migration Problem example problem
Gel Migration Problem

DNA Marker # of
Base Pairs
(bp)		 Migration
Distance
(cm)
500 base pairs 500 3.31
1,000 base pairs 1000 3.05
2,000 base pairs 2000 2.79
3,000 base pairs 3000 2.64
5,000 base pairs 5000 2.45
10,000 base pairs 10000 2.19
Unknown ? ? 2.73

The standard DNA ladder and unknown DNA strand listed in the table were separated using an agarose gel
Estimate the number of base pairs of the unknown DNA strand.
Note: answers need to be within 11% of the correct number to be correct.
 

Matching Molecular Weight to Protein Ladder Bands

Click to show Matching Molecular Weight to Protein Ladder Bands example problem

Lane 1 shows a simulated Kaleidoscope-style pre-stained protein ladder.

Match each colored band to its molecular weight.

Your Choice Prompt
Drop Your Choice Here 1.  colored band
Drop Your Choice Here 2.  colored band
Drop Your Choice Here 3.  colored band
Drop Your Choice Here 4.  colored band
Drop Your Choice Here 5.  colored band

Drag one of the choices below:

  • A. 75 kDa
  • B. 37 kDa
  • C. 10 kDa
  • D. 25 kDa
  • E. 150 kDa
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