How are the nucleus and the nucleolus different?
The nucleolus is a structure found in the nucleus of cells and it forms around specific chromosomal regions in the nucleus of eukaryotic cells, and is made up of proteins and ribonucleic acids. Its main function is to transcribe ribosomal RNA (rRNA) and combine it with proteins to form incomplete ribosomes.
The nucleolus occupies up to about 25% of the volume of the cell nucleus.
The nucleus is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, (histones) to form chromosomes.
The function of the nucleus is to maintain the integrity of these genes and to control the activities of the cell by regulating gene expression — the nucleus is, therefore, the control center of the cell.
Also, difference between nucleus and nucleolus is their appearance. The main structures making up the nucleus are the nuclear envelope, a double membrane that encloses the entire organelle and isolates its contents from the cellular cytoplasm, and the nucleoskeleton, a network within the nucleus that adds mechanical support, much like the cytoskeleton, which supports the cell as a whole.
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