Which structure synthesizes ribosomes and is located in the nucleus?

Which structure synthesizes ribosomes and is located in the nucleus?

• A. Nucleolus
• B. Nucleus
• C. Ribosome
• D. Mitochondrion

Answer: (A)

The nucleolus is the region inside the nucleus where ribosomal components are made and assembled. Here, the genes for ribosomal RNA (rRNA) are transcribed, rRNA is processed, and ribosomal proteins imported from the cytoplasm are combined to form the small and large ribosomal subunits. Once assembled, these subunits are exported to the cytoplasm to join and function in protein synthesis. The nucleus overall houses DNA, but the actual production and initial assembly of ribosomal subunits happen specifically in the nucleolus. The mitochondrion and the ribosome itself aren’t the sites of ribosome synthesis.

The nucleolus is the region inside the nucleus where ribosomal components are made and assembled. Here, the genes for ribosomal RNA (rRNA) are transcribed, rRNA is processed, and ribosomal proteins imported from the cytoplasm are combined to form the small and large ribosomal subunits. Once assembled, these subunits are exported to the cytoplasm to join and function in protein synthesis. The nucleus overall houses DNA, but the actual production and initial assembly of ribosomal subunits happen specifically in the nucleolus. The mitochondrion and the ribosome itself aren’t the sites of ribosome synthesis.