Most abundant RNA in a cell is `:`

Options

A. rRNA
B. mRNA
C. tRNA
D. snRNA

Answer

To determine the most abundant RNA in a cell, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Types of RNA**:
- There are several types of RNA present in cells, including ribosomal RNA (rRNA), messenger RNA (mRNA), transfer RNA (tRNA), and small nuclear RNA (snRNA).

2. **Understand the Functions of Each RNA Type**:
- **rRNA**: This is a structural component of ribosomes, which are essential for protein synthesis.
- **mRNA**: This carries genetic information from DNA to the ribosomes for protein synthesis.
- **tRNA**: This helps in translating the mRNA sequence into a polypeptide chain by bringing the appropriate amino acids.
- **snRNA**: This is involved in RNA splicing and processing.

3. **Analyze the Abundance of Each RNA Type**:
- In a rapidly growing mammalian cell:
- rRNA makes up approximately 80% of the total RNA.
- mRNA constitutes about 5% of the total RNA.
- tRNA accounts for around 15% of the total RNA.
- snRNA is present in smaller quantities (100-200 nucleotides).

4. **Compare the Percentages**:
- From the percentages, it is clear that rRNA is the most abundant type of RNA, significantly outnumbering mRNA and tRNA.

5. **Conclusion**:
- Based on the analysis, the most abundant RNA in a cell is ribosomal RNA (rRNA).

### Final Answer:
The most abundant RNA in a cell is **rRNA (ribosomal RNA)**.

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