module 7

Digestive system overview

Digestive tract

long tube that food travels in

esophagus = anus

It’s job is to break down food, absorbs nutrients, and get rid of waste

Mucosa

mucous membrane lining the alimentary canal

• protects organs (from stomach acid)

• Absorbs nutrients (especially in small intestine)

• produces mucus and enzymes to help digestion

inner most layer (inside lining of digestive system)

superficial layer

beginning & end are stratified squamous

middle is simpler columnar

Submucosa

a connective tissue layer located deep to the mucosa layer

second layer ( helps mucosa do it’s job)

Muscular layer

3 muscle layer that moves food through digestive system

bilayer of smooth muscle located deep to the submucosa; performs peristalsis and segmentation in the alimentary canal

movement along tract (move food forward using wake like movements called peristalsis)

Serosa

deepest layer (of the alimentary canal for abdominopelvic organs)

protect outer covering

help organs in place

knows as the visceral peritoneum

only in abdominopelvic cavity

Gastrointestinal tract

pathway (series of organs) that food passes through when in the digestive system

long tube in your body that food travels through (job is too digest food, obsorbes nutrients, and remove waste) = it takes the good and get rid of the bad

alimentary canal

pathway (series of organs) that food passes through when in the digestive system

path food goes

Accessory Digestive organs

Digestive organs that participate in the digestive functions but food does not pass through

Peritoneum

serous membrane that surrounds many abdominopelvic organs

it’s like a protective wrap around abdominal organs

Visceral peritoneum

The inner layer of the abdominopelvic serous membrane

it’s a thin wrap that covers your organs

Parietal Peritoneum

The outer layer of the abdominopelvic serous membrane

it’s like a lining on the inside of your belly wall (not on the organs)

adventitia

the deepest layer of the alimentary canal for structures outside of the reach of the peritoneum (oral cavity, pharynx, thoracic, esophagus, parts of the large intestine)

it’s like a glue or support tissue that holds organs to nearby structures

Peristalsis

Coordinated, rhythmic smooth muscle contractions in the gastrointestinal tract that help in the movement of food along the tract

it’s like a squeezing wave that moves food forward