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Nucleolus
This EM shows the subdivisions of the nucleolus. The palest region, the fibrillar center, contains the nucleolar organizing regions of multiple chromosomes; the pars fibrosa (dense fibrillar component) contains the newly transcribed rRNA; and the pars granulosa contains maturing ribosomes. This nucleolus is partially surrounded by perinucleolar heterochromatin. 35,000x
![Nucleolus <p>This EM shows the subdivisions of the nucleolus. The palest region, the fibrillar center, contains the nucleolar organizing regions of multiple chromosomes; the pars fibrosa (dense fibrillar component) contains the newly transcribed rRNA; and the pars granulosa contains maturing ribosomes. This nucleolus is partially surrounded by perinucleolar heterochromatin. 35,000x</p>](https://digitalhistology.org/wp-content/uploads/2017/05/C.S.N-17-1-ping.png)
Nucleolus
This EM shows the subdivisions of the nucleolus. The palest region, the fibrillar center, contains the nucleolar organizing regions of multiple chromosomes; the pars fibrosa (dense fibrillar component) contains the newly transcribed rRNA; and the pars granulosa contains maturing ribosomes. This nucleolus is partially surrounded by perinucleolar heterochromatin. 35,000x
![- Nucleolar organizing center (fibrillar center) <p>This EM shows the subdivisions of the nucleolus. The palest region, the fibrillar center, contains the nucleolar organizing regions of multiple chromosomes; the pars fibrosa (dense fibrillar component) contains the newly transcribed rRNA; and the pars granulosa contains maturing ribosomes. This nucleolus is partially surrounded by perinucleolar heterochromatin. 35,000x</p>](https://digitalhistology.org/wp-content/uploads/2017/05/C.S.N-17-2-ping.png)
- Nucleolar organizing center (fibrillar center)
This EM shows the subdivisions of the nucleolus. The palest region, the fibrillar center, contains the nucleolar organizing regions of multiple chromosomes; the pars fibrosa (dense fibrillar component) contains the newly transcribed rRNA; and the pars granulosa contains maturing ribosomes. This nucleolus is partially surrounded by perinucleolar heterochromatin. 35,000x
![- Pars fibrosa <p>This EM shows the subdivisions of the nucleolus. The palest region, the fibrillar center, contains the nucleolar organizing regions of multiple chromosomes; the pars fibrosa (dense fibrillar component) contains the newly transcribed rRNA; and the pars granulosa contains maturing ribosomes. This nucleolus is partially surrounded by perinucleolar heterochromatin. 35,000x</p>](https://digitalhistology.org/wp-content/uploads/2017/05/C.S.N-17-3-ping.png)
- Pars fibrosa
This EM shows the subdivisions of the nucleolus. The palest region, the fibrillar center, contains the nucleolar organizing regions of multiple chromosomes; the pars fibrosa (dense fibrillar component) contains the newly transcribed rRNA; and the pars granulosa contains maturing ribosomes. This nucleolus is partially surrounded by perinucleolar heterochromatin. 35,000x
![- Pars granulosa <p>This EM shows the subdivisions of the nucleolus. The palest region, the fibrillar center, contains the nucleolar organizing regions of multiple chromosomes; the pars fibrosa (dense fibrillar component) contains the newly transcribed rRNA; and the pars granulosa contains maturing ribosomes. This nucleolus is partially surrounded by perinucleolar heterochromatin. 35,000x</p>](https://digitalhistology.org/wp-content/uploads/2017/05/C.S.N-17-4-ping.png)
- Pars granulosa
This EM shows the subdivisions of the nucleolus. The palest region, the fibrillar center, contains the nucleolar organizing regions of multiple chromosomes; the pars fibrosa (dense fibrillar component) contains the newly transcribed rRNA; and the pars granulosa contains maturing ribosomes. This nucleolus is partially surrounded by perinucleolar heterochromatin. 35,000x
![Perinucleolar heterochromatin <p>This EM shows the subdivisions of the nucleolus. The palest region, the fibrillar center, contains the nucleolar organizing regions of multiple chromosomes; the pars fibrosa (dense fibrillar component) contains the newly transcribed rRNA; and the pars granulosa contains maturing ribosomes. This nucleolus is partially surrounded by perinucleolar heterochromatin. 35,000x</p>](https://digitalhistology.org/wp-content/uploads/2017/05/C.S.N-17-5-ping.png)
Perinucleolar heterochromatin
This EM shows the subdivisions of the nucleolus. The palest region, the fibrillar center, contains the nucleolar organizing regions of multiple chromosomes; the pars fibrosa (dense fibrillar component) contains the newly transcribed rRNA; and the pars granulosa contains maturing ribosomes. This nucleolus is partially surrounded by perinucleolar heterochromatin. 35,000x
![Nuclear envelope <p>This EM shows the subdivisions of the nucleolus. The palest region, the fibrillar center, contains the nucleolar organizing regions of multiple chromosomes; the pars fibrosa (dense fibrillar component) contains the newly transcribed rRNA; and the pars granulosa contains maturing ribosomes. This nucleolus is partially surrounded by perinucleolar heterochromatin. 35,000x</p>](https://digitalhistology.org/wp-content/uploads/2017/05/C.S.N-17-6-ping.png)
Nuclear envelope
This EM shows the subdivisions of the nucleolus. The palest region, the fibrillar center, contains the nucleolar organizing regions of multiple chromosomes; the pars fibrosa (dense fibrillar component) contains the newly transcribed rRNA; and the pars granulosa contains maturing ribosomes. This nucleolus is partially surrounded by perinucleolar heterochromatin. 35,000x