Mammalian Digestive System

Alimentary canal (plus accessory glands)

Mouth

where food and air enter the body

Pharynx

muscular tube that connects the mouth and nose to the esophagus, trachea, and larynx, allowing us to breathe, swallow, and speak

Lungs

central organs of the respiratory system

Esophagus

long, hollow organ which transports food from the mouth to the digestive system

Stomach

Main location for food storage

• pepsin breaks down food

  • chief cells: pepsinogen

• Parietal cell, release HCl

Duodenum

first part of the small intestine, which receives partially digested food from the stomach and begins the absorption of nutrients.

Small intestine

Major organ of digestion and absorption

→ simple molecules

→ water

Colon

Serves to recover water

receive chyme, the mix of digested food from the small intestine, and further digest it into a firm stool that passes from the body

Cecum

houses microorganisms

Appendix

houses good bacteria

Rectum

Temporary storage site for feces.

Absorption of excess water from fecal material.

Thickening of stool through water absorption and mixing with mucus.

Moving stool toward the anus for elimination.

Anus

external opening of the rectum. It is located inside the intergluteal cleft and serves as the exit point for waste elimination during defecation

Large intestine

Houses the colon, cecum, appendix, rectum, and anus

Salivary glands

amylase: start of polysaccharide digestion

Liver

forms bile

Bile

Breaks down fats and eliminates waste products

Gall bladder

storage of vile

Pancreas

Releases:

• Proteases and other enzymes

• bicarbonate

• nucleoases, amylase, and lipase

Peristalsis

movement of food in a path (one way)

Sphincters

regulate passage of material