Question:

DNA strands on a gel stained with ethidium bromide when viewed under UV radiation, appear as :

Updated On: Aug 6, 2024
  • Yellow bands
  • Bright orange bands
  • Dark red bands
  • Bright blue bands
Hide Solution
collegedunia
Verified By Collegedunia

The Correct Option is B

Solution and Explanation

DNA strands on a gel stained with ethidium bromide when viewed under UV radiation appear as bright orange bands. They appear orange because ethidium bromide releases an orange fluorescence at 605nm when exposed to UV light.
So, the correct option is (B): Bright orange bands.
Was this answer helpful?
0
1

Concepts Used:

DNA Fingerprinting

​​DNA fingerprinting, also called DNA typing, DNA profiling, genetic fingerprinting, genotyping, or identity testing, in genetics, method of isolating and identifying variable elements within the base-pair sequence of DNA.

The procedure of DNA Fingerprinting:

The procedure for creating a DNA fingerprint consists of first obtaining a sample of cells, such as skin, hair, or blood cells, which contain DNA. The DNA is extracted from the cells and purified. In Jeffreys’s original approach, which was based on restriction fragment length polymorphism (RFLP) technology, the DNA was then cut at specific points along the strand with proteins known as restriction enzymes. The enzymes produced fragments of varying lengths that were sorted by placing them on a gel and then subjecting the gel to an electric current (electrophoresis): the shorter the fragment, the more quickly it moved toward the positive pole (anode). The sorted double-stranded DNA fragments were then subjected to a blotting technique in which they were split into single strands and transferred to a nylon sheet. The fragments underwent autoradiography in which they were exposed to DNA probes—pieces of synthetic DNA that were made radioactive and that bound to the minisatellites. A piece of X-ray film was then exposed to the fragments, and a dark mark was produced at any point where a radioactive probe had become attached. The resultant pattern of marks could then be analyzed.