Answer: The external submucosa I'd the layer of the alimentary canal that contain the blood vessels,glands and nerve plexus that help to regulate digestive activity.
Explanation:
The alimentary canal or gastrointestinal tracts is the organ in the body that helps to break down ingested food into pieces that can be absorbed by human body and expels unwanted food as wastes. The alimentary canal consists of structures from mouth to the anus. The alimentary canal have four distints layers which are the the mucosa, submucosa,muscular layer and serosa.
The mucosa is the inner layer of alimentary canal and it surrounds the lumen. This layer have direct contact with digested food.
The submucosa consists of dense connective tissues, blood vessers, glands and nerve plexus. It regulate digestive activity.
The muscular layer consists of inner circular layer and longitudinal circular layer. It prevents food from going backward.
The serosa is the external layer of the alimentary canal and iits have several connective tissues.
