Digestion Peritoneal Cavity Layers of a GI Organ

Digestion Peritoneal Cavity Layers of a GI Organ Oral Cavity Swallowing Esophagus Marieb 23

The Abdominopelvic Cavity Peritoneal Cavity Parietal Peritoneum Visceral Peritoneum Mesentery

Mesenteries Doubled Layered Serosa Dorsal Mesenteries Ventral Mesenteries

Digestive Processes Mechanical Digestion Chemical Digestion Absorption Propulsion

Digestive Themes Anatomical Variation Environmental Variation Neuronal control Locally Hormonal Control Globally

Innermost Digestive Organ Layers Mucosa Submucosa Muscularis externa Serosa Outermost The Small Intestine

Mucosa: Epithelium Secretion and absorption Mucus secreting cells

Mucosa: Lamina Propria and M. Mucosa Capillaries Sensory Neurons Immune cells Muscularis mucosa

Submucosa Elastic Connective tissue Blood vessels Lymph vessels and nodes Nerve fibers

Muscularis Externa 2 Smooth Muscle Layers

Serosa: Areolar Connective Tissue Fluid and salt retention Immune cells Fat storage Visceral Peritoneum

Digestion Begins in the Mouth Mastication Salivary glands

Saliva: Lubrication, Digestion, Immunity H 2 O Mucin Amylase

From Mouth to Pharynx Bolus Pharynx Naso. Oro. Laryngo-

Pharynx to Esophagus Pharynx common passage for food and air Esophagus Trachea Epiglottis

Swallowing: Voluntary and Involuntary Phases Tongue forces bolus into pharynx Epiglottis blocks trachea Pharynx and Esophageal muscles contract Upper Esophageal Sphincter Opens

Esophagus: “Food Carrier” Upper esophageal sphincter Lower esophageal sphincter Esophageal Hiatus

Esophagus: Mucosa and Submucosa Stratified Squamous Folds Esophageal glands

Esophagus: Muscularis externa Skeletal Muscle Smooth Muscle

Esophagus to Stomach Peristalsis 2 -8 seconds No Digestion No Absorption