Question Detail
Question
When a large proportion of a cell's ribosomes are attached to the endoplasmic reticulum, it is a sign that the cell is specialized to: A. Manufacture glucose for storage B. Manufacture phospholipids for cell growth C. Perform photosynthesis with high efficiency D. Manufacture proteins for export
Correct Answer
Option D is the correct answer.
Detailed Explanation
Ribosomes attached to the rough endoplasmic reticulum (RER) synthesize proteins that are destined for secretion (export) from the cell, for incorporation into the cell membrane, or for delivery to other organelles like lysosomes. Cells with extensive RER, such as pancreatic cells producing digestive enzymes, are specialized for protein secretion.
Hint
The 'rough' ER is involved in making proteins that need further processing and packaging for delivery outside the cell.