Florida Biology EOC Practice Test 2025 – 400 Free Practice Questions to Pass the Exam

The rough endoplasmic reticulum (RER) plays a crucial role in the synthesis and processing of proteins. It is characterized by the presence of ribosomes on its surface, which give it a "rough" appearance. These ribosomes are the sites of protein translation, where amino acids are assembled into proteins based on the genetic instructions carried by mRNA. Once synthesized, proteins may undergo further modifications within the RER, such as folding and glycosylation, which are essential for their proper function and distribution. This gives the rough endoplasmic reticulum a primary function in both the making and initial processing of proteins, aligning with the response chosen.

Other options correspond to different cellular functions: detoxification is largely managed by the smooth endoplasmic reticulum and other organelles like the liver's peroxisomes; storage of food, water, and minerals pertains to structures like vacuoles; and enzymatic reactions can occur in various locations within the cell but are not specifically a function of the rough endoplasmic reticulum.