Details of Nucleus

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 Ø  Structure of Nucleus: Chemically they are made of nucleic acid and protein. It contains some protein, trace of DNA and RNA, little amount of Co-enzyme and other materials. Physically they are made by the following parts: - Nuclear membrane, Nucleoplasm, Nucleolus and Chromosome

Ø  Nuclear membrane: The double layered transparent membrane, which make the outer covering of the nucleus is the nuclear membrane The outer membrane porous but the inner one is not. Chemically the membrane is made of protein and lipid.

Ø  Function: The main function of this membrane.is to keep the nucleoplasm, chromosome and the nucleus distinct from cytoplasm. Transportation and communication between internal materials and cytoplasm is also done through this membrane.

chromosomes are present in it.

Ø Nucleoplasm: It is a transparentand dense fluid bounded by nuclearmembrane. Nucleolus andchromosomes are present in it.

Ø  Function: It holds chromosomes and performs various organic functions.

Ø  Nucleolus: The denser, small and round body found in the nucleus is the nucleolus. Every nucleus normally contains a single nucleolus. Nucleolus is usually attached to a certain area of a Particular chromosome. The region of chromosome where it remain attached is called `secondary constriction'.

Ø  Chemical composition: The main compositions of the nucleolus are protein, RNA and a trace of DNA.

Ø  Physical structure: Nucleolus is usually divided into three parts namely fibrous, granular and matrix.

Ø  Function: To synthesise various types of DNA and protein and preserve them. 

Chromosome: In every nucleus there is a definite number of chromosomes according to the characteristic of definite species. It can be seen under microscope after proper staining, only in a dividing cell. Every chromosome contains one or more centromere, one chromonema or more chromonemata and some chromosome may have satellite. Chromosome bears a number of gene and genes are responsible for expressing characteristics of different species.

Ø  Chemical composition of chromosome: Chemically each chromosome is composed of DNA, RNA, Histon and non-histon protein. Besides, some calcium and magnesium are also present here.

Ø  Function: Chromosome is the bearer and carrier of hereditary properties of the organism.