Explanation:
gan Major functions Other functions
Mouth
Ingests food
Chews and mixes food
Begins chemical breakdown of carbohydrates
Moves food into the pharynx
Begins breakdown of lipids via lingual lipase
Moistens and dissolves food, allowing you to taste it
Cleans and lubricates the teeth and oral cavity
Has some antimicrobial activity
Pharynx
Propels food from the oral cavity to the esophagus
Lubricates food and passageways
Esophagus
Propels food to the stomach
Lubricates food and passageways
Stomach
Mixes and churns food with gastric juices to form chyme
Begins chemical breakdown of proteins
Releases food into the duodenum as chyme
Absorbs some fat-soluble substances (for example, alcohol, aspirin)
Possesses antimicrobial functions
Stimulates protein-digesting enzymes
Secretes intrinsic factor required for vitamin B12 absorption in small intestine
Small intestine
Mixes chyme with digestive juices
Propels food at a rate slow enough for digestion and absorption
Absorbs breakdown products of carbohydrates, proteins, lipids, and nucleic acids, along with vitamins, minerals, and water
Performs physical digestion via segmentation
Provides optimal medium for enzymatic activity
Accessory organs
Liver: produces bile salts, which emulsify lipids, aiding their digestion and absorption
Gallbladder: stores, concentrates, and releases bile
Pancreas: produces digestive enzymes and bicarbonate
Bicarbonate-rich pancreatic juices help neutralize acidic chyme and provide optimal environment for enzymatic activity
Large intestine
Further breaks down food residues
Absorbs most residual water, electrolytes, and vitamins produced by enteric bacteria
Propels feces toward rectum
Eliminates feces
Food residue is concentrated and temporarily stored prior to defecation
Mucus eases passage of feces through colon
