Figure 2: Amber vesicle of Aplysia californica. (a) Vesicle containing large vacuoles of hydrated protein. The amber vesicle is surrounded by cells rich in rough endoplasmic reticulum (RER cells) and is adjacent to a vesicle cell (see also (f)). ((b) and (c)) Protein contained within membrane bound vacuoles (arrows) in an amber vesicle. (d) Amber vesicle nucleus adjacent to the vesicle lumen which is filled with hydrated protein. (e) Fusion of protein vacuole membrane with central vacuole membrane (arrow) that fills the vesicle lumen. (f) Vesicle cell with large nucleus and dense cytoplasm. Circled area enlarged as Figure 3(a). cv, central vacuole; pv, protein vacuole; hp, hydrated protein; m, muscle; n, nucleus; rer, rough endoplasmic reticulum rich cell; vc, vesicle cell. Scale bars: (a) = 5 μm; (b) = 100 nm; (c) = 200 nm; (d) = 1 μm; (e) = 100 nm; (f) = 2 μm.