For effective separation of DNA fragments via gel electrophoresis, the following sequential steps are necessary:
Step 1: Staining with Ethidium Bromide
Initially, DNA fragments are stained with ethidium bromide. This compound attaches to DNA, rendering it visible under UV illumination.
Step 2: UV Light Exposure
Subsequently, the DNA-containing gel is exposed to UV light. This causes the ethidium bromide-bound DNA to fluoresce, making it discernible for subsequent examination.
Step 3: Elution Process
Following visualization, DNA fragments are eluted from the gel. Elution is the process of extracting DNA from the agarose gel for subsequent applications or analyses.
Step 4: DNA Fragment Migration to Anode
Upon application of an electric field, the negatively charged DNA fragments migrate towards the anode. This directed movement facilitates size-based separation, as smaller fragments traverse the gel at a higher velocity.
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