GENERAL HISTOLOGY

Detailed explanation-1: -The most prominent substructure within the nucleus is the nucleolus (see Figure 8.1), which is the site of rRNA transcription and processing, and of ribosome assembly. As discussed in the preceding chapter, cells require large numbers of ribosomes to meet their needs for protein synthesis.

Detailed explanation-2: -The nucleolus is the most prominent structure in a cell nucleus. It is the site of ribosomal RNA (rRNA) transcription, pre-rRNA processing and ribosome subunit assembly.

Detailed explanation-3: -The nucleolus is the largest subnuclear compartment of the cell that forms around regions of chromosomes containing stretches of tandem repetitive ribosomal RNA (rRNA) genes, known as nucleolar organizer regions (NORs).

Detailed explanation-4: -The Nucleolus-The nucleolus is a membrane-less organelle within the nucleus that manufactures ribosomes, the cell’s protein-producing structures. Through the microscope, the nucleolus looks like a large dark spot within the nucleus.