Nucleus Structure and Function.

1. NUCLEUS AND ITS STRUCTURE
Presented By - Mr. Amit S . Olambe

2. Introduction
1
Presentation Overview
Components of Nucleus
3
Structure of Nucleus
2
Function of Nucleus
4

3. INTRODUCTION
 A Nucleus is defined as a double-membrane eukaryotic cell organelles
that contain genetic material.
 It is most important organelles of a eukaryotic cell that control over all
cell activities.
 Robert Brown (1833) Discovered Nucleus.
 Nucleus is found in almost all cells except mature red blood cells of
mammals.
 Shape of Nucleus is normally releted with shape of the cell. It is usually
spherical or oval shape mostly located in the centre of cell.
 The average size is about 5-7 u.
 Most cell have a single Nucleus they are said to be mononucleate, cell
having two nuclei are called Binucleate cells.

4. Structure of Nucleus

5. Nuclear Membrane
1
Components of Nucleus
Nucleoplasm
3
Nucleolus
2
Chromatin Material
4

6. Nuclear Membrane

7. Nucleolus
 The nucleolus is the distinct structure present in the nucleus of eukaryotic cell.
 It is composed of RNA & proteins which form around specific chromosomal region
 It is one of the main components of the Nucleus.
 The size of the nucleolus is releted with synthetic activity of the cell.

8. Nucleoplasm
 It is the jelly like fluid present inside the nucleus.
 It is transparent, semi-solid , granular & slightly acidophilic.
 It is mainly composed of Nucleoprotein but also contain various inorganic and organic
substances.
 It shows presence of following molecules
a) Nucleic acid- DNA & RNA
b) Protein
c) Enzymes
d) Lipids & Minerals

9. Chromatin Material
 It is mainly made up of DNA and histone protein.
 It can be stained with basic dyes such as basic fuchsin.
 Its main function is to carry hereditary information from one generation to another
generation.
 The chromatin was discovered by Walther Flemming in 1878.
 There are two types of chromatin
1. Euchromatin- The chromatin that remains dispersed and stains lightly during
interphase is called Euchromatin. It contains transcriptionally active DNA
2. Heterochromatin- The chromatin that remains tightly coiled during interphase is
called heterochromatin. It stains deeply and it is transcriptionally inactive.

10. Function of Nucleus
1. Nucleus controls metabolic activities in the cell.
2. Nucleus acts as a store House of the cells genome and is the chief controlling centre of
the cell.
3. Synthesis and regulations of activities of enzymes are controlled by the nucleus.
4. Stores genetic information (DNA & RNA)
5. Both the subunits of ribosome are synthesized in nucleus.
6. Has a vital role in protein synthesis (Ribosomal Protein)
7. t-RNA and m-RNA are transcribed from DNA present in the nucleus.

11. THANK YOU