During protein synthesis, amino acid gets attached to tRNA with the help of

Options

A. mRNA
B. Aminoacyl synthetase
C. Ribosome
D. rRNA

Answer

### Step-by-Step Solution:

1. **Understanding the Role of tRNA**: Transfer RNA (tRNA) is a type of RNA that plays a crucial role in protein synthesis. It is responsible for bringing the appropriate amino acids to the ribosome, where proteins are synthesized.

2. **Amino Acid Attachment**: The process of attaching an amino acid to tRNA is essential for protein synthesis to occur. Each tRNA molecule is specific to one amino acid.

3. **Enzyme Involved**: The enzyme that facilitates the attachment of an amino acid to its corresponding tRNA is called **aminoacyl-tRNA synthetase**. This enzyme catalyzes the reaction that links the amino acid to the tRNA.

4. **Importance of the Reaction**: The attachment of the amino acid to tRNA is a critical step because, without this attachment, the tRNA cannot deliver the amino acid to the ribosome, and thus protein synthesis cannot initiate.

5. **Initial Amino Acid**: The first amino acid that is typically added during the initiation of protein synthesis is methionine. This is important as it marks the start of the protein chain.

6. **Types of tRNA**: There are about 20 different types of tRNA, each corresponding to one of the 20 different amino acids used in protein synthesis.

7. **Structure of tRNA**: The structure of tRNA can be described in two dimensions (2D) and three dimensions (3D). The 2D structure resembles a cloverleaf shape, while the 3D structure is L-shaped, which is important for its function.

### Final Answer:
During protein synthesis, amino acids get attached to tRNA with the help of **aminoacyl-tRNA synthetase**.

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