Which organelle is responsible for modifying, sorting, and packaging proteins for export from the cell?

Which organelle is responsible for modifying, sorting, and packaging proteins for export from the cell?

• A. Ribosome
• B. Endoplasmic reticulum
• C. Lysosome
• D. Golgi apparatus

Answer: (D)

Proteins destined for export are processed in the Golgi apparatus. After being synthesized in the rough endoplasmic reticulum, proteins are transported to the Golgi, where they are chemically modified, such as by adding carbohydrate chains. The Golgi then sorts these proteins to their correct destinations and packages them into vesicles that bud off and travel to the plasma membrane to release the cargo outside the cell. Ribosomes are the sites of protein synthesis, not processing for export. The endoplasmic reticulum handles synthesis and initial folding of proteins, with some early modifications, but the Golgi is where the major modification, sorting, and packaging for export occur. Lysosomes are involved in breaking down and digesting cellular waste, not exporting proteins.

Proteins destined for export are processed in the Golgi apparatus. After being synthesized in the rough endoplasmic reticulum, proteins are transported to the Golgi, where they are chemically modified, such as by adding carbohydrate chains. The Golgi then sorts these proteins to their correct destinations and packages them into vesicles that bud off and travel to the plasma membrane to release the cargo outside the cell.

Ribosomes are the sites of protein synthesis, not processing for export. The endoplasmic reticulum handles synthesis and initial folding of proteins, with some early modifications, but the Golgi is where the major modification, sorting, and packaging for export occur. Lysosomes are involved in breaking down and digesting cellular waste, not exporting proteins.