Histology of the Alimentary Canal

What are the four basic layers of the walls (tunics) of the alimentary canal

Mucosa, submucosa, muscalaris externa, and serosa

What is the mucosa of the digestive tract

innermost lining of digestive tract

What is the function of the mucosa of the digestive tract

SECRETE mucus, digestive enzymes, and hormones; ABSORB the end products of digestion; PROTECT against infectious disease

What type of epithelium is the mucosa of the digestive tract

Simple columnar epithelium

What are the three layers of the mucosa

epithelium, lamina propria, muscularis mucosae

What is the function of the epithelium of the mucosa

Slippery substance that protects organs from enzymes and helps food move

What is the lamina propria in the epithelium

It nourishes the epithelium and contains lymphoid follicles that protect against bacteria and pathogens

What is the muscalaris mucosae in the digestive tract

It enhances absorption and secretion

What is the submucosa in the digestive tract

connective tissue layer that contains blood vessels, nerves, lymphatic vessels, and glands. Its elastic, so organs can regain their normal shapes

What is the muscalaris externa?

It surrounds the submucosa and is responsible for argumentation and peristalsis

What is the serosa

The thin, double-layered membrane that covers the walls of the ventral body cavity and the outer surfaces of the organs it contains