**Question:** Termination process of protein synthesis is performed by all except

A. ribosomes
B. tRNA
C. DNA
D. enzymes

**Core Concept:**
The process of protein synthesis involves the assembly of amino acids into a polypeptide chain under the control of genetic information encoded in DNA. This process occurs in the ribosomes, where three main components are involved: mRNA (messenger RNA), tRNA (transport RNA), and rRNA (ribosomal RNA). The termination process refers to the events that mark the end of protein synthesis and release the newly synthesized polypeptide chain.

**Why the Correct Answer is Right:**
The correct answer is **D. enzymes**, because enzymes are not involved in the termination process of protein synthesis. Enzymes are biological catalysts that accelerate chemical reactions within cells, but they do not directly participate in protein synthesis or its termination.

**Why Each Wrong Option is Incorrect:**
A. **Ribosomes** are the cellular organelles responsible for protein synthesis, and termination is a process occurring within ribosomes.
B. **tRNA** (transport RNA) plays a crucial role in protein synthesis by carrying amino acids to the ribosome, but it is not directly involved in termination.
C. **DNA** (deoxyribonucleic acid) is the genetic material that carries genetic information but is not involved in the termination process.

**Clinical Pearl / High-Yield Fact:**
Understanding the correct answer helps distinguish between different cellular components involved in protein synthesis. This knowledge is essential for medical students and clinicians to accurately comprehend cellular processes, as well as for diagnosing and treating various diseases related to protein synthesis disorders or imbalances.