So I was just reading that whether heterochromatin or euchromatin is more abundant in a particular human cell depends on how active that cell is. But considering that most of the 25,000 or so genes in the human genome are transcriptionally inactive in any given cell, how is it possible for cellular activity to affect the chromatin structure to a degree that significantly alters how a nucleus looks on microscopic images? Since, after all, whether the cell is active or not will only affect little of the chromatin.
And since most of the genome is inactive, shouldn't it be in a heterochromatic form, and thus most of the chromatin in any given cell will be heterochromatin?
(I know this is not true, but I was wondering why)