MT: Digestive System I will know the locations and functions of the major parts of the digestive system.

Major Parts of Digestive System Mouth Salivary glands Esophagus Stomach Small Intestine Large Intestine Liver Gallbladder Pancreas

Mouth Lips, cheeks, and tongue all have mucous membranes that secrete enzyme to break down food Tongue and teeth used in mastication to start mechanical digestion

Salivary Glands Parotid glands: located under ears Submandibular Glands: located under mandible in back Sublingual Gland: located under tongue They all secrete saliva which has enzymes to break down food ~1 liter of saliva a day

Esophagus Collapsible tube ~ 10 inches From mouth to stomach Has layers of skeletal muscle on near throat and smooth muscle toward stomach

Stomach Stretchable pouch that can hold ~ 1 to 1.5 liters 2 sphincters close stomach off Glands release hydrochloric acid in stomach (need sphincters to contain acid) Muscle contracts to thrash food around and break into smaller pieces

Small Intestine ~ 22 feet long, 1 inch diameter of coiled tubes Have villi (fingerlike projections) that increase the surface area for absorption of nutrients

Large Intestine ~ 6 feet long, 2.5” diameter Parts: cecum, colon, rectum, anus Absorb water from food to form feces Secrete mucous to lubricate feces while defecating

Liver Large gland (3-4 lbs) 2 lobes; right lobe is bigger than left Breaks down proteins, fat, & carbs Stores iron, Vit A, B12, and D Secretes bile (bile necessary to digest fat) detoxifier

Gallbladder 3-4 inch green sac located underneath the liver Secretes bile (bile helps body absorb fat)

Pancreas Grayish pink gland located near stomach and small intestine Secretes enzymes to help with digestion Secrete insulin ( a hormone that maintains blood sugar level.)