Question

1. the nuclear envelope has passages for substances moving into and out of the nucleus. these passages are called nuclear pores and they are made by proteins that are inserted into the plasma membrane that makes up the nuclear envelope. these proteins are assembled by which of the following?

a. free ribosomes
b. the nucleus
c bound ribosomes
d. nuclear pores

Explanation:

• Free ribosomes synthesize proteins that function in the cytoplasm.
• The nucleus is the site of DNA storage and transcription, not protein assembly.
• Nuclear pores are the structures in question, not the protein - assembling entities.
• Bound ribosomes (attached to the endoplasmic reticulum) synthesize proteins that are inserted into membranes (like the plasma membrane of the nuclear envelope).

Answer:

C. Bound ribosomes