Distinguish the form and nature of chromosomes between dividing and non dividing cells

The form and nature of chromosomes varies during the life cycle of the cell and they differ between dividing and non dividing cells. 
Non-dividing cells are in the Interphase when the most of the chromatin (complex of DNA and proteins that forms chromosomes) is decondensed and throughout the nucleus. In that form it is called Euchromatin.
In dividing cells it is called Heterochromatin when the most of the chromatin is condensed and chromosomes are noticeable.

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