Acinus acinar epithelium: simple Structure. cuboidal or pyramidal cells myoepithelial cell basal membrane Serous acini Be divided into Mucous acini Mixed aciniAcinus : ▪ acinar epithelium: simple cuboidal or pyramidal cells ▪ myoepithelial cell ▪ basal membrane Structure: Be divided into Serous acini Mucous acini Mixed acini