The four layers of the digestive tract are:
It is the outermost single layer of flat cells.
Function: It protects the inner layer.
It is made up of thick, non-striated muscle fibres arranged into three layers forming the outer layer of longitudinal muscle, middle layer of circular muscles and inner layer of oblique muscles.
Function: Churns food.
It consists of connective tissue containing blood vessels, nerve fibres and lymphatic vessels.
4. Muscular mucosa:
Thin layer of non-striated muscle fibres.