Why hnRNA is required to undergo splicing?

Explanation

### Step-by-Step Solution

1. **Understanding hnRNA**: hnRNA stands for heterogeneous nuclear RNA. It is the initial transcript synthesized from DNA during the process of transcription. This form of RNA is not yet mature and contains both coding and non-coding sequences.

2. **The Role of Splicing**: Splicing is a crucial process that modifies hnRNA to produce mature mRNA. During splicing, non-coding regions known as introns are removed, and the coding regions known as exons are joined together. This transformation is essential for the proper expression of genes.

3. **Importance of Exons and Introns**: In the context of mRNA, exons are the sequences that encode proteins, while introns do not code for proteins. If introns are not removed, the resulting mRNA would contain non-coding sequences that could disrupt the translation process, leading to non-functional or harmful proteins.

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