STRUCTURE AND FUNCTION OF NUCLEUS
Structure:
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Nucleus is situated in the cytoplasm of the cell.
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Usually, it is round but many different shaped nuclei can be seen in some cells.
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It is surrounded by two porous membranes called nuclear membranes which remain continuous with the Endoplasmic Reticulum.
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Within the nuclear membrane is present a liquid substance called nucleoplasm.
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Nucleoplasm contains two types of chromatin material: Heterochromatin and Euchromatin.
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Chromatin fibres are thin thread-like structures composed of DNA and proteins.
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These fibres condense to form short thick chromosomes during cell division and become visible.
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DNA molecules transfer hereditary information from one generation to the next.
Function:
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Nucleus is one of the most important components of the cell.
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It controls the various metabolic activities of the cell. Therefore, it is called the control centre of the cell.
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If the nucleus is removed, the cell ultimately dies.
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It controls cell division.
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It is involved in transmission of hereditary characters from parents to off springs.