Biochemistry Proteins directed to which of the following organelles are synthesized by ribosomes attached to the rough endoplasmic reticulum? A Lysosomes B Mitochondria C Nucleus D Peroxisomes 💡 Explanation Proteins directed to which of the following organelles are synthesized by ribosomes attached to the rough endoplasmic reticulum? ✓ Correct Answer: A. Lysosomes