SCIENCE
CELL BIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Nucleolus
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Nucleus
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Nuclear membrane
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Nuclear matrix
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Detailed explanation-1: -They are the site of most of the synthesis of ribosomal RNA (rRNA) and assembly of ribosome subunits. Nucleoli organize at the end of mitosis and consist of repeated clusters of ribosomal DNA (rDNA) genes and processing molecules responsible for producing ribosome subunits.
Detailed explanation-2: -Molecules of rRNA are synthesized in a specialized region of the cell nucleus called the nucleolus, which appears as a dense area within the nucleus and contains the genes that encode rRNA.
Detailed explanation-3: -So, the correct answer is-nucleolus.
Detailed explanation-4: -mRNA levels are determined by two distinct processes: transcription, catalyzed by RNA polymerase II (Pol II), and mRNA decay. Transcription occurs in the nucleus whereas the major mRNA decay pathways operate in the cytoplasm.