tRNA combines with
**Question:** tRNA combines with
A. Ribosomes
B. mRNA
C. Proteins
D. DNA
**Core Concept:** tRNA (transport RNA) is a type of RNA molecule that plays a crucial role in protein synthesis in cells. tRNA molecules are responsible for delivering amino acids to the ribosomes, where they are incorporated into the growing polypeptide chain.
**Why the Correct Answer is Right:** tRNA combines with ribosomes, which are the sites of protein synthesis in cells. Ribosomes are the sites where mRNA (messenger RNA) serves as a template for the assembly of amino acids into proteins. tRNA molecules facilitate this process by binding to specific codons on the mRNA and delivering the corresponding amino acid to the ribosome.
**Why Each Wrong Option is Incorrect:**
A. Ribosomes: While ribosomes are involved in protein synthesis, tRNA does not combine with ribosomes directly. Instead, tRNA binds to ribosomes to deliver amino acids for protein synthesis.
B. mRNA (messenger RNA): mRNA carries the genetic information for protein synthesis but does not directly interact with tRNA. tRNA binds to specific codons on the mRNA to deliver amino acids to the ribosome.
C. Proteins: tRNA does not combine with proteins. tRNA delivers amino acids to the ribosome for protein synthesis, and proteins are the final products of this process.
D. DNA (Deoxyribonucleic Acid): DNA is the genetic material that stores hereditary information, but it does not combine with tRNA. tRNA is responsible for delivering amino acids to the ribosome during protein synthesis.
**Clinical Pearl:** Understanding the role of tRNA in protein synthesis is essential for medical students and practicing clinicians alike. This knowledge is crucial for understanding the molecular mechanisms of cellular processes, drug actions, and therapeutic implications.