Which organelle is embedded on the surface of the rough endoplasmic reticulum (rough ER)?

• A. Ribosome
• B. Lysosome
• C. Mitochondrion
• D. Golgi apparatus

Answer: (A)

Verified step by step guidance

1. Understand the structure and function of the rough endoplasmic reticulum (rough ER). The rough ER is a network of membranes within the cell that is involved in protein synthesis and transport. Its surface appears 'rough' due to the presence of certain organelles.
2. Recall that ribosomes are the organelles responsible for protein synthesis. They are composed of RNA and proteins and can either float freely in the cytoplasm or attach to the surface of the rough ER.
3. Differentiate ribosomes from other organelles listed in the options. Lysosomes are involved in digestion and waste processing, mitochondria are responsible for energy production, and the Golgi apparatus is involved in modifying, sorting, and packaging proteins.
4. Recognize that the rough ER is specifically associated with ribosomes, which are embedded on its surface, giving it the 'rough' appearance under a microscope.
5. Conclude that the correct answer is ribosome, as it is the organelle embedded on the surface of the rough ER, enabling the synthesis of proteins directly into the ER lumen.