Anatomy of the Digestive System
What are the two organ groups of the digestive system?
The alimentary canal or gastrointestinal tract, and accessory digestive organs
What are the six essential activities?
Ingestion, propulsion, mechanical digestion, chemical digestion, absorption, and defecation
Tongue
Gloss (o)
Four basic layers
Mucosa, submucosa, muscularis externa, serosa
What are the cell types of the gastric glands?
Mucous neck cells, parietal cells, chief cells, and enteroendocrine cells
What consists of the alimentary canal?
Mouth, pharynx, esophagus, stomach, small intestine, and large intestine
Where does propulsion take place?
Oropharynx
Cheek
Bucc (o)
What tissue makes up the serosa layer?
What do the chief cells secrete?
Inactive enzyme pepsinogen
What consists of the accessory digestive organs?
What is mechanical digestion?
Physically breaking down food substances into smaller particles
Teeth
Dent (o)
What is the inner most layer of the four basic layers?
Mucosa
What is the function of enteroendocrine cells?
Secrete chemical messengers into the lamina propria
What is the function of saliva?
It moistens the food for swallowing, contains salivary amylase, and converts starch to maltose.
What is the function of absorption?
Molecules that result from chemical digestion that pass through the cell membrane of the small intestine
Gums
Gingiv (o)
What is the function of the mucosa?
Secretes mucus, digestive enzymes, and hormones. Protects against infectious disease, and absorbs end products of digestion
What do parietal cells secrete?
Gastrin or HCL
What are the three parts of the small intestine?
Duodenum, jejunum, ileum
Where does digestion start?
Oral cavity
Small intestine
Jejun/o
What are the three sublayers of the mucosa?
Epithelium, lamina propria, and muscularis mucosae
What do mucous neck cells secrete?
Thin acidic mucus