in contrast , no significant differences were seen in the volume densities of rough endoplasmic reticulum , free ribosomes , secretion granules , smooth endoplasmic reticulum , or mitochondria in randomly selected prostatic epithelial cells of dogs 1.5 to 9 years of age , whether or not the prostates were hyperplastic .
C0230779
rough endoplasmic reticulum
C1179933
free ribosomes