National League for Nursing (NLN) Science Practice Exam

Gene expression is a fundamental biological process that encompasses the transformation of genetic information from DNA into functional products, primarily proteins. This process involves two critical steps: transcription and translation. During transcription, a specific segment of DNA is copied into messenger RNA (mRNA), which serves as a template for the synthesis of proteins. Once the mRNA is formed, it undergoes translation, where ribosomes read the mRNA sequence and assemble amino acids in the correct order to form proteins.

Understanding this process is essential, as proteins play crucial roles in virtually all cellular functions, from structural components to enzymes that catalyze biochemical reactions. This is why the statement regarding transcription of DNA into mRNA and translation into proteins effectively captures the essence of gene expression.

Other options do not encompass the full scope of gene expression. For instance, the idea of protein synthesis without RNA is fundamentally incorrect, as RNA is essential for translating the genetic code into proteins. Focusing solely on DNA replication ignores the roles of RNA and proteins in gene expression, while discussing only RNA processing overlooks the initial transcription step necessary for mRNA formation. Thus, understanding the complete cycle of transcription and translation is crucial for grasping the concept of gene expression in biological systems.