Alimentary Canal

• What are the primary organs are part of the digestive system?

  • Mouth
  • Pharynx
  • Esophagus
  • Stomach
  • Small Intestine
  • large Intestine
• The alimentary canal is also known as the

  Gastrointestinal Tract (GI Tract)
• Starts at the mouth and ends at the end of the large intestine, the anus
• Mechanical digestion is accomplished by the teeth and tongue

  Mouth
• produce enzymes that begin chemical digestion

  Salivary glands
• The area behind the nose and mouth

  Pharynx
• Extends from the pharynx to the stomach; about 25 cm long

  Esophagus
• Muscle contractions contribute to mechanical digestion

  Stomach
• Secretes enzymes that digest protein

  Stomach
• J-shaped muscular organ that expands from the inferior end of the esophagus

  Stomach
• has a layer of oblique muscle in addition to the circular and longitudinal layers. Three layers allow for churning and mixing of food as it moves through the stomach

  Stomach
• The body’s major digestive organ

  Small Intestine
• Almost all absorption occurs in the

  Small Intestine
• Digestion of all nutrients is completed

  Small Intestine
• Longest part of the GI tract; about 3-4 m long and 2.5 cm in diameter


  Small Intestine
• 3 subdivisions of the small intestine:

  • duodenum
  • jejunum
  • ileum