What is the functional connection between the nucleolus, nuclear pores, and the nuclear membrane?

• A. The nuclear pores are connections between the nuclear membrane and the endoplasmic reticulum that permit ribosomes to assemble on the surface of the ER.
• B. The nucleolus contains messenger RNA (mRNA), which crosses the nuclear envelope through the nuclear pores.
• C. Membrane of the endoplasmic reticulum is produced in the nucleolus and leaves the nucleus through the nuclear pores.
• D. None of the listed responses is correct.
• E. Subunits of ribosomes are assembled in the nucleolus and pass through the nuclear membrane via the nuclear pores.

Answer: (E)

Verified step by step guidance

1. Understand the role of the nucleolus: The nucleolus is a region within the nucleus where ribosomal RNA (rRNA) is synthesized and combined with proteins to form ribosomal subunits.
2. Identify the function of nuclear pores: Nuclear pores are large protein complexes that span the nuclear envelope, allowing the transport of molecules between the nucleus and the cytoplasm.
3. Recognize the role of the nuclear membrane: The nuclear membrane, also known as the nuclear envelope, is a double membrane structure that encloses the nucleus, providing a barrier between the nucleoplasm and the cytoplasm.
4. Connect the nucleolus and nuclear pores: Ribosomal subunits assembled in the nucleolus are transported through the nuclear pores to the cytoplasm, where they participate in protein synthesis.
5. Clarify the correct functional connection: The correct connection is that subunits of ribosomes are assembled in the nucleolus and pass through the nuclear membrane via the nuclear pores.