. What is the role of ribosomes and Golgi body?

Ribosomes are the cellular factories responsible for protein synthesis, translating genetic information from messenger RNA (mRNA) into functional proteins by linking amino acids in the precise sequence specified by the genetic code. Found either free-floating in the cytoplasm or attached to the rough endoplasmic reticulum, ribosomes consist of two subunits (large and small) made of ribosomal RNA and proteins. Free ribosomes typically produce proteins for use within the cell itself, such as enzymes for metabolic pathways, while membrane-bound ribosomes synthesize proteins destined for secretion, membrane incorporation, or packaging into organelles. Every protein in a cell—from structural components to enzymes to signaling molecules—begins its existence on a ribosome, making these organelles absolutely essential for life.

The Golgi apparatus (Golgi body or Golgi complex) functions as the cell's processing, packaging, and distribution center, receiving proteins and lipids from the endoplasmic reticulum, modifying them, and sorting them to their final destinations. This organelle consists of a stack of flattened membrane sacs (cisternae) where proteins undergo modifications such as glycosylation (adding sugar groups), phosphorylation, and proteolytic cleavage. The Golgi then packages these modified molecules into membrane-bound vesicles targeted for specific locations—secretory vesicles for export outside the cell, lysosomes for intracellular digestion, or the plasma membrane for incorporation. In secretory cells like pancreatic cells producing insulin or salivary glands producing enzymes, the Golgi is highly developed. Together, ribosomes and Golgi bodies form a production line: ribosomes manufacture the raw proteins, which are then refined, packaged, and shipped by the Golgi apparatus.