Question

what is the correct sequence for the layers in the walls of the alimentary canal from innermost to outermost?
multiple choice
submucosa, mucosa, serosa, muscular layer
mucosa, muscular layer, serosa, submucosa
mucosa, submucosa, muscular layer, serosa
serosa, muscular layer, mucosa, submucosa

Explanation:

The walls of the alimentary canal have four main layers. The innermost layer is the mucosa which is in direct contact with the contents of the canal. Next is the submucosa which contains blood vessels, nerves, etc. Then comes the muscular layer (responsible for peristalsis). The outermost layer is the serosa (a protective layer).

Answer:

Mucosa, submucosa, muscular layer, serosa.