Question

what is the main function of the rough endoplasmic reticulum in a plant cell? to fill the space between the cell membrane and the nucleus to direct cell activities by sending instructions to different parts of the cell to help ribosomes make proteins to make lipids

Explanation:

1. Analyze each option:

• "to fill the space between the cell membrane and the nucleus" describes the cytoplasm, not the rough endoplasmic reticulum (RER).
• "to direct cell activities by sending instructions to different parts of the cell" is the function of the nucleus (containing DNA with instructions).
• "to help ribosomes make proteins": The rough ER has ribosomes attached to its surface. These ribosomes synthesize proteins, and the rough ER provides a site and helps in the process of protein synthesis (e.g., folding, modification of newly made proteins).
• "to make lipids" is the function of the smooth endoplasmic reticulum, not the rough ER.

Answer:

to help ribosomes make proteins