Which membrane-bound organelle is the site of protein and lipid synthesis?

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

Answer: (A)

Verified step by step guidance

1. Begin by identifying the function of each organelle listed in the options. Understanding their roles will help determine which one is responsible for protein and lipid synthesis.
2. The Endoplasmic Reticulum (ER) is divided into two types: Rough ER and Smooth ER. The Rough ER is studded with ribosomes and is primarily involved in protein synthesis. The Smooth ER lacks ribosomes and is involved in lipid synthesis.
3. The Golgi Apparatus is responsible for modifying, sorting, and packaging proteins and lipids for secretion or delivery to other organelles.
4. Mitochondria are known as the powerhouse of the cell, primarily involved in energy production through ATP synthesis, not directly in protein or lipid synthesis.
5. Lysosomes contain digestive enzymes and are involved in breaking down waste materials and cellular debris, not in the synthesis of proteins or lipids.