the ultrastructural organization of the active animal 's neurones is characterized by morphological alteration pointing to an increased metabolic activity , viz. , an increased number of nucleoli , an enlarged surface of nuclear membrane and an increase in the nuclear membrane pores , appearance of a zone of free ribosomes near the nuclear membrane , changing the structure of cytosomes , abundant granular endoplasmic reticulum , increase in the number of mitochondria .
C1179933
free ribosomes
C0230779
granular endoplasmic reticulum