Which organelle modifies, packages, and sorts proteins for secretion or delivery to other organelles?

• A. Ribosome
• B. Lysosome
• C. Endoplasmic Reticulum
• D. Golgi Apparatus

Answer: (D)

Proteins that are meant to be secreted or delivered to other parts of the cell are processed by the Golgi apparatus. After proteins are made in the endoplasmic reticulum and travel in vesicles to the Golgi, this organelle modifies them—adding carbohydrate tags and other finishing touches—tags them for their specific destinations, and then packages them into new vesicles for export or delivery to target locations such as lysosomes or the plasma membrane. This combination of modification, packaging, and sorting for secretion or delivery is the hallmark of the Golgi apparatus.

Ribosomes synthesize proteins but don’t modify or sort them; the endoplasmic reticulum handles synthesis and initial folding and modification rather than final sorting; lysosomes contain digestive enzymes and break down materials, not prepare proteins for secretion.