The lamina propria is full of blood vessels and lymphatic channels. The muscular layer is made up of easy muscle fibers, with an outer layer of longitudinal muscle mass, an interior layer of circular muscle mass, and oblique muscle mass fibers between. The outer layer, the adventitia, is a thin http://www.v-skiacademy.com/module/content/content.php?co_id=m_charge&mcode=jam3hvl4