Vaculated cytoplasm with enlarged atypical nuclei having corse granular chromatin and conspicous nucleoli
Answers
The nucleus is the largest and the most essential storage compartment of DNA in a functional living cell. This organelle contains the self-perpetuating nucleic acid (DNA) that codes for various kinds of proteins synthesized in the cytoplasm of the cell.
When observed under a microscope, the nucleus within the cells can either present as open phase nucleus or a closed phase nucleus.
Open phase nucleus is also called as vesicular nucleus. This is seen in an actively proliferating or actively synthesizing cell in which nucleus contains prominent nucleoli. It can exhibit marked variation in size and shape, occasionally with very large and bizarre forms. Usually no more than 2-3 nucleoli per cell are seen. Their number, size and shape generally are species specific and relate to the synthetic activity of the cell.[1]
In a closed phase nucleus, the nucleus is small with a defined outline and uniform nuclear chromatin that indicates that the cell is in resting phase. In such cells, the nucleolus can be seen only during interphase.
The most prominent substructure within the nucleus is the nucleolus. It is a dense non-membrane bound structure observed during interphase in a normal cell, because it dissipates during cell division.[1]
The nucleolus is the site of rRNA synthesis, transcription and processing. It is designed to fulfill the need for large-scale production of rRNA and assembly of the ribosomal subunits.[2] Ultrastructurally, it consists of components like fibrillar center, dens fibrillar component, granular component, condensed chromatin that is inactive, interstices and nucleolar vacuole.[3]
rRNAs are essential for the formation of ribosomes. This involves the assembly of the ribosomal precursor RNA with both ribosomal proteins and 5S rRNA.