Question

Ribosomal RNA is actively synthesized in

• A. Lysosomes
• B. Nucleolus
• C. Nucleoplasm
• D. Ribosomes

Answer 1

The correct option is B

Nucleolus

The correct option is B.

The explanation for the correct option:

1. Ribosomes are made up of 60 percent ribosomal RNA and 40 percent ribosomal protein.
2. The nucleolus is a spherical body of the nucleus that enlarges during protein synthesis in most eukaryotes.
3. The nucleolus is primarily made up of RNA and proteins so they play an active role in ribosomal RNA production.

The explanation for incorrect options:

Option A:

1. Lysosomes are also referred to as suicide bags since they're involved in autolysis.
2. There are no ribosomes in them as a result of which, they aren't engaged in RNA production.

Option C:

1. A nucleoplasm is a form of protoplasm comprised primarily of water, a combination of molecules, and dissolved ions.
2. Its main function is to sustain chromosomes and nucleoli; it does not participate in RNA production.

Option D:

1. Ribosomes are spherical structures that can be seen in association with the rough endoplasmic reticulum.
2. They are involved in the synthesis of proteins.

Final Answer: Ribosomal RNA is actively synthesized in the nucleolus.