Which cellular structure is primarily responsible for packaging, modifying, and sorting proteins for secretion?

Which cellular structure is primarily responsible for packaging, modifying, and sorting proteins for secretion?

• A. Rough ER
• B. Golgi apparatus
• C. Lysosome
• D. Peroxisome

Answer: (B)

Proteins that will be secreted are processed along the secretory pathway, and the Golgi apparatus is the station where they are modified, sorted, and packaged into vesicles for export. After synthesis in the rough endoplasmic reticulum, proteins arrive at the Golgi in transport vesicles. Inside the Golgi, enzymes add or trim sugar groups and other markers, refining the protein’s structure and tagging it for its destination. The Golgi then sorts the proteins and packages them into new vesicles that bud off from its trans face. These vesicles carry the proteins to the plasma membrane for secretion, or to other destinations such as the cell membrane or lysosomes, depending on the targeting signals. In short, the Golgi is the key organelle that handles the final preparation, tagging, and packaging of proteins for secretion.

Proteins that will be secreted are processed along the secretory pathway, and the Golgi apparatus is the station where they are modified, sorted, and packaged into vesicles for export. After synthesis in the rough endoplasmic reticulum, proteins arrive at the Golgi in transport vesicles. Inside the Golgi, enzymes add or trim sugar groups and other markers, refining the protein’s structure and tagging it for its destination. The Golgi then sorts the proteins and packages them into new vesicles that bud off from its trans face. These vesicles carry the proteins to the plasma membrane for secretion, or to other destinations such as the cell membrane or lysosomes, depending on the targeting signals. In short, the Golgi is the key organelle that handles the final preparation, tagging, and packaging of proteins for secretion.