Question

What is the functions of layers lining the human alimentary canal ?

Answer 1

Mucosa-protection,secretion and absorption
Sub-mucosa-nourishes surrounding tissues,transports absorbed materials
Muscular layer-movements of the tube and it's contents
Serosa-protection and lubrication

Answer 2

Four layers of Alimentary canal are :-

$\textbf{1) Serosa}$

It is the outermost layer made up of simple squamous epithelium and have connective of tissues.
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$\textbf{2) Musclaries}$

These are smooth muscles and have large number of connective tissue. It consists of inner circular and outer longitudinal.
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$\textbf{3) Sub-Mucosa}$

It controls the working of mucosa. It is a rich connective tissue richly supplied with lymph and blood vessels.

Meissner's plexus is present between muscular coat and mucosa.
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$\textbf{4) Mucosa}$

The innermost layer of sub-mucosa is Mucosa. It helps in absorption and contraction. It had irregular foldings in stomach called rugae villi in small intestine.
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