Question

In Southern blotting, DNA molecules are immobilized on ______

A) gold beads.
B) nitrocellulose membranes.
C) silicon chips.
D) agarose.
E) paper.

Answer 1

DNA molecules in Southern blotting are immobilized on nitrocellulose or nylon membranes, not on gold beads, silicon chips, agarose, or paper. This technique is used to detect specific DNA sequences.

Step-by-step explanation:

In Southern blotting, DNA molecules are immobilized on nitrocellulose membranes or nylon membranes. This method is used to detect specific DNA sequences within a sample.

The procedure involves separating DNA fragments by agarose gel electrophoresis, and then transferring them to the membrane through capillary action. Once immobilized, the DNA fragments are probed with labeled DNA probes that are complementary to the sequence of interest. The probes usually contain radioactive or fluorescent tags to facilitate detection. This technique is distinct from Northern blotting, which involves RNA, and Western blotting, which involves proteins.