The endoderm.
ENDODERM
Endoderm
Ectoderm
Mucous membranes line the digestive and respiratory tracts.
Mucus
The Epithelium
The Epithelium
The digestive and respiratory systems share the mouth and the pharynx. The respiratory system also includes the glottis, trachea, bronchi, bronchioles and alveoli.Buccal cavity? Pharynx?pharynxThe Larynx
pharynx( and for those who didn't know its the very back of your mouth)
Some animals have relatively short digestive tracts because they are carnivores. Herbivores need longer digestive tracts than carnivores in order to digest cellulose.
The mucous membrane is epithelium. It lines the passageways and chambers that communicate with the exterior. The exterior is known as digestive, respiratory, reproductive, and urinary tracts.
The mucous membrane lines all body cavities that open to the exterior, such as those of hollow organs of the respiratory, digestive, urinary, and reproductive tracts.
incomplete
Any body area that has an outlet to the out side is covered in a mucous membrane: respiratory tact. digestive tract, urinary tract, even the membrane that surrounds the orbit of the eye (eye ball).
Smooth muscles are usually found (1. in the walls of blood vessels; (2. around hollow organs such as the urinary bladder; (3. and in layers around the respiratory, Circulatory, Digestive, and Reproductive tracts.