Nucleus and nucleolar

1. Nucleus and Nucleolar
Presented by : Patel Rinku
MSc sem :1
CBO : 403
Department of life sciences,
H. N.G.U. , Patan.

2. Contents
 Nucleus :
• Introduction
• Ultra structure chemical nature
 Nucleolar :
• Introduction
• Ultra structure chemical nature
 Nucleolar chromosome

3. Nucleus
Introduction :
• The nucleus was the first organelle to be
discovered. The nucleus also known as the
control centre is a membrane enclosed
organelle found in eukaryotic cells.
• It contains most of the cell's genetic material.
• The main structures making up the nucleus is
the nuclear envelope a double membrane that
encloses the entire organella.

5. Ultra structure
• Nucleus is the controlling centre where the
master molecule DNA directs the entire activity
of the cell.
Nuclear membrane :
• The nuclear membrane covers the nucleus.
• It allows material to flow in and out of small
pores.

7. Chemical nature
• The nucleus contains mainly nucleoproteins
composed of nucleic acid and proteins, besides
enzymes and inorganic salts.
• The following is the percentage of different
components of nucleus of mammalin liver cells in
interphase, determined by spectrophotometric
analysis :
DNA 9% Residual protein 14%
RNA1% other acidic proteins 65%
Histone protein 11%

9. Nucleolar
• The nucleolus is a non - membrane bound
structure Composed of proteins and nucleic
acids found within the nucleus.
• The ribosomal RNA is transcribed in the
nucleolus.

11. Ultra structure
• Three major Components of the nucleolus
are recognized :the fibrillar center (FC), the
dense fibrillar Component (DFC), and the
granular Component (GC).
• Transcription of the rDNA Occurs in the FC.
• The GC Contains the protein
nucleophosmin.

13. Chemical nature
• The main Compositions of the nucleolus are
protein, RNA and a trace of DNA.
• This structure is made up of proteins and
ribonucleic acids (RNA).
• Its main function is to rewrite ribosomal
RNA (rRNA) and combine it with proteins.
• Nucleolus is usually divided into three parts
namely fibrous, granular and matrix.

14. Nucleolar chromosome
• Chromosomes are long string - like a structures.
• They are coiled to fit into the nucleus.
• Chromosomes are made of DNA.
• They are the genetic information of the
organism.
• Also called chromatin when it is uncoiled.

16. References
 Cell biology, Genetics, Molecular Biology,
Evolution and Ecology
P. S. Verma and agarwal
https://www.ncbi.nlm.nih.gov

17. Thank you