SnRNPs pronounced as Snurps are small nuclear ribonucleoproteins ( RNA+Proteins). They are used for splicing of hnRNA in the nucleus. The RNA found within each snRNP is known as small nuclear RNA (snRNA). They are usually about 150 nucleotides long.
Therefore, option 1 is the correct answer.

Tailoring of hnRNA is done by snurps (small nuclear ribonucleoproteins).

Explanation:

What is hnRNA?

hnRNA (heterogeneous nuclear RNA) is the primary transcript of RNA synthesized by RNA polymerase II during transcription. It is also called pre-mRNA because it undergoes several modifications before it becomes mature mRNA.

What is tailoring of hnRNA?

Tailoring of hnRNA is a process of modifying the primary transcript of RNA to form a mature mRNA. It involves several steps, such as:

1. Capping: The addition of a 7-methyl-guanosine cap at the 5' end of hnRNA to protect it from degradation.

2. Splicing: The removal of introns (non-coding regions) from hnRNA and joining of exons (coding regions) to form a continuous coding sequence.

3. Polyadenylation: The addition of a poly(A) tail at the 3' end of hnRNA to increase its stability and facilitate its export from the nucleus to the cytoplasm.

How is tailoring of hnRNA done?

Tailoring of hnRNA is done by snurps (small nuclear ribonucleoproteins). Snurps are RNA-protein complexes that are involved in splicing of hnRNA.

Snurps contain two types of RNA molecules: small nuclear RNA (snRNA) and small nucleolar RNA (snoRNA). SnRNA forms the catalytic core of snurps, while snoRNA guides the modification of ribosomal RNA (rRNA) and transfer RNA (tRNA).

The splicing process involves the recognition of specific sequences at the intron-exon boundaries by snurps. The snurps bind to these sequences and bring the intron and exon together to form a spliceosome. The spliceosome then cuts the hnRNA at the intron-exon junctions and joins the exons to form mature mRNA.

Conclusion:

Tailoring of hnRNA is a complex process that involves several steps, such as capping, splicing, and polyadenylation. Snurps play a crucial role in splicing of hnRNA by recognizing specific sequences at the intron-exon boundaries and bringing the intron and exon together to form a spliceosome.