Animal Digestion

intercellular digestion

inside the cell - used by single celled organisms (protists) & sponges

• food is ingested in a food vacuole using phagocytosis

extracellular digestion

outside the cell - used by hydra, flatworms like planaria

incomplete digestive systems

gastrovascular cavity

alimentary canal

• oral cavity

• pharynx

• esophagus

• stomach

• small intestine

  • large intestine

accessory organ

• salivary glands

• pancreas

• liver

• gall bladder

salivary amylase

breaks down sugars

esophagus (peristalsis)

process where food breaks down esophagus

stomach (pepsin)

breaks down protein

pyloric sphincter

a muscular valve that opens to allow food to pass from the stomach to the top of the small intestine

small intestine

major organ for digestion & absorption

pancreas

produces digestive enzymes & an alkaline solution that changes the pH of the digestive contents in the duodenum

pancreatic amylase

breaks down starch

proteins

trypsin & chymotrypsin

nucleic acids

nucleases break down DNA & RNA

absorption of nutrients

the longer your intestines are, the more nutrients you will absorb

digestive circulation

food travels to small intestine, then to the liver

large intestines

• stores water & wastes

• major function - reabsorbs water that was not absorbed by the small intestines, producing feces

• intestinal bacteria inhabit the colon-producing vitamins K & B

ruminant

a large group of herbivores with a four-chambered stomach

hindgut

the part of the vertebrate digestive tract comprising the colon and rectum

foregut

the anterior part of the digestive tract of a vertebrate embryo that develops into the pharynx, esophagus, stomach, and extreme anterior part of the intestine

coprophagia

the practice of eating stool (feces)