In 1909, Western Union and ADT came under the control of American Telephone & Telegraph Company (AT&T). ADT began to expand into new areas, such as fire alarms and security alarms between 1910 and 1930, but was kept separate from AT&T's Holmes alarm business. ADT became a publicly owned company in the 1960s.
It has moist membranes. Many, but not all (urinary), secrete mucous. Serous: Lines open body cavities that are closed to the exterior body surface. composed of simple squamous epithelium resting on thin layer of areolar connective tissue.
It is exposed to air= dry membrane. It is considered an epithelial membrane. Mucous: Lines all body cavities that open to the exterior body surface. It is often adapted for secreation and absorbtion. Located in stratified squamous epithelium (mouth esophogus) and simple columnar epithelial (rest of digestive tract). It rests on loose connective tissue called Lamina propria.