A DNA ladder contains pieces of DNA of known sizes and may be used to determine the size of a DNA fragment of unknown length Question 22 options: TrueFalse
Added by Gregory L.
Step 1
A DNA ladder is a mixture of DNA fragments of known lengths that are used as a reference in gel electrophoresis. Show more…
Show all steps
Your feedback will help us improve your experience
Adi S and 71 other Biology educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
A common practice when separating DNA molecules by size on an agarose gel is to load a size ladder in one of the sample wells. A size ladder is a mixture of DNA fragments of known size. For example, a size ladder may contain a mixture of DNA fragments that are 500 base pairs, 1000 base pairs and 2000 base pairs in length. How might running the size ladder adjacent to experimental DNA samples help a scientist to interpret the results of an experiment?
Adi S.
Why was a DNA ladder loaded into the gel electrophoresis cartridge? The DNA ladder contained a know amount of DNA fragments. The length of these DNA ladder fragments (measured by the number of 'base pairs' in each fragment) was also known. Therefore we could theoretically compare the known lengths of the "DNA ladder fragments" to the fragments of the two viral DNA samples. The DNA ladder helps the other unknown viral DNA samples climb up and travel through the gel. DNA looks like a twisted ladder. Ladders are cool! The DNA ladder contained a know amount of DNA fragments. However the length of these DNA ladder fragments was not known. Therefore we could theoretically compare the lengths of the "DNA ladder fragments" to the fragments of the two viral DNA samples to see if they were made of the same DNA.
Suman K.
When performing gel electrophoresis, why do molecular biologists add a "ladder" made up of nucleic acids or proteins of known size? To make sure the dye included in the sample buffer doesn't interfere with the movement of the DNA fragments that are being studied. The DNA fragments being studied would be invisible without the ladder. To help determine the size of each DNA fragment after the separation has occurred. To help DNA fragments move through the gel more rapidly.
Maitreya E.
Recommended Textbooks
Biology for AP Courses
Objective Biology for NEET
Introduction to General, Organic and Biochemistry
Transcript
Watch the video solution with this free unlock.
EMAIL
PASSWORD