What is the name of the region of cells between a stem’s epidermis and its set of vascular bundles? This is usually a compact parenchyma tissue, but in some aquatic angiosperms that live submerged in lakes or oceans, this region has what type of special modification? Would you hypothesize that this region is especially thick or thin in desert plants such as cacti or plants that have succulent water storage tissues (you must think about this yourself, as the answer is not in the text).