Molecular genetics primarily focuses on what aspect of DNA?

• A. Population distribution
• B. Gene expression mechanisms
• C. Phenotypic traits
• D. Evolutionary theory

Answer: (B)

Molecular genetics is fundamentally concerned with the mechanisms by which genes are expressed and regulated at the molecular level. This field specifically investigates how genetic information is transcribed into RNA and subsequently translated into proteins, which are critical processes that determine an organism’s phenotype. Understanding gene expression mechanisms involves analyzing regulatory sequences, transcription factors, and post-transcriptional modifications, and how these elements influence the activity of genes under different conditions.

In contrast, population distribution pertains to the genetic variations and frequencies within populations over time, which falls under the realm of population genetics rather than molecular genetics. Phenotypic traits, while influenced by gene expression, are more about the observable characteristics resulting from the interaction of genes and the environment, making it a broader topic that includes aspects beyond just molecular interactions. Evolutionary theory focuses on the mechanisms behind the changes in allele frequencies over generations, which involves genetics but is more about the overall impact of genetic variation on species adaptation and survival, rather than the intricate details of gene expression and regulation. Thus, the emphasis of molecular genetics on gene expression mechanisms distinguishes it as the primary focus of the field.