The endoplasmic reticulum is scattered in the cytoplasm. They are like tiny tube-nets with innumerable branches. Its face is smooth or uneven. They maintain contact between the cell components by creating a delicate structure within the cytoplasm. Osmium cannot be dyed with tetra-oxide. The gallbladder is near the nucleus. They are stratified , the layers are flattened and densely packed. The face is always smooth. They are involved in the synthesis and secretion of cell compounds. Osmium can be dyed with tetra-oxide.