Digestion and the Digestive System

Front

Mechanical digestion breaks down large pieces of food into smaller ones without changing chemical composition.

Back

This includes actions like chewing.

Front

Mastication

Back

Mechanical breakdown of solid particles, mixes them with saliva; functions as an organ of speech and sensory reception.

Front

Cheeks

Back

Form the lateral walls of the mouth; contain muscles for facial expression and chewing.

Front

Serous cells

Back

Produce a watery fluid containing salivary amylase; splits starch and glycogen into disaccharides.

Front

Pharynx

Back

Muscular walls function in swallowing; extends from nasal cavity to esophagus.

Front

Esophagus

Back

Tubular organ that extends from the pharynx to the stomach

Front

First stage of swallowing

Back

Voluntary stage where saliva is mixed with chewed food, forming a bolus

Front

Third stage of swallowing

Back

Peristalsis transports food in the esophagus to the stomach

Front

Layers of stomach muscle

Back

Inner circular layer, outer longitudinal layer, some portions have innermost layer of oblique fibers

Front

Pepsinogen

Back

Inactive form of pepsin; secreted by chief cells