Which of the following RNAs have clover leaf structure?

Options

A. transfer RNA
B. messenger RNA
C. ribosomal RNA
D. heterogenous RNA

Answer

To answer the question "Which of the following RNAs have a clover leaf structure?", let's analyze the options step by step.

### Step 1: Identify the Types of RNA
We have four types of RNA to consider:
1. Transfer RNA (tRNA)
2. Messenger RNA (mRNA)
3. Ribosomal RNA (rRNA)
4. Heterogeneous RNA (hnRNA)

### Step 2: Analyze Transfer RNA (tRNA)
- tRNA is known for its clover leaf structure.
- It functions as an adapter molecule that links mRNA to amino acids during protein synthesis.
- The structure consists of several loops and stems, including:
- Acceptor stem with a CCA tail for amino acid attachment.
- D loop containing dihydrouridine.
- Anticodon loop that pairs with the codon on mRNA.
- T loop containing pseudouridine.

### Step 3: Analyze Messenger RNA (mRNA)
- mRNA is a single-stranded RNA molecule.
- It does not have a clover leaf structure; instead, it has a linear structure that carries genetic information from DNA to the ribosome for protein synthesis.

### Step 4: Analyze Ribosomal RNA (rRNA)
- rRNA is a component of ribosomes, which are made up of two subunits.
- It does not exhibit a clover leaf structure; rather, it has a complex three-dimensional structure.

### Step 5: Analyze Heterogeneous RNA (hnRNA)
- hnRNA refers to the primary transcript of RNA before it is processed into mRNA.
- It is also single-stranded and does not have a clover leaf structure.

### Conclusion
Based on the analysis, the only RNA that has a clover leaf structure is **Transfer RNA (tRNA)**.

### Final Answer
The correct answer is **Transfer RNA (tRNA)**.

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