Animal	Ingestion	Digestion	Excretion
Porifera	filter feeders: collar cells pump water through body, screening out food.	collar cells digest, send nutrients to amoebocytes, which transport materials to other cells	water current removes undigested material
Cnidaria	capture prey with nematocysts. causes tentacles to move toward mouth, sweeping prey into gut.	cells lining gastrovascular cavity secrete strong enzymes to digest food. nutrients are absorbed by cells.	waste left in cavity leaves by same opening. other waste diffuses into water.
Platyhelminthes	scavenger, predator. mouth in middle of body, ventral side. extends pharynx out of mouth, sucks in food. passes to branched intestine.	nutrients absorbed into body through intestinal wall.	undigested food excreted through mouth and pharynx. chemical waste, excess water eliminated through flame cells connected to ducts running the length of the body.
Nematoda	anterior mouth	digestive tube	posterior anus
Annelida	take in soil through mouth as they burrow; sucked in by pharynx, passes through esophagus	stored in crop, ground up in gizzard, breaking up organic matter. food digested, absorbed by intestine	undigested food passes food out of anus. nephridia: get rid of nitrogenous waste.
Gastropoda	radula scrapes food	complete digestive tube	anus over head
Bivalvia	filter feeders: cilia on gills; beats to incurrent siphon. leaves through excurrent siphon.	mucus traps plankton, cilia beat to mouth. travels to stomach. absorbed in intestine.	waste leaves through anus
Cephalopoda	predator; capture with tentacles, radula, sharp beak to kill and eat.	complete digestive tube	waste leaves through anus
Echinodermata	tube feet obtain food; can open clam shells. turns stomach inside out.	enzymes in stomach digest clam in its shell. stomach withdraws and food is absorbed.	waste diffuses through skin gills
Crustacea	trap food with chelipeds, tear with maxillae and maxillipeds	food passes through esophagus to stomach: chitinous teeth grind up digestive fluids into body of prey	green glands remove wastes; undigested food passes through intestine and out anus
Arachnida	drink fluids that result from digestive fluids	external digestion: inject digestive fluids into body of prey	Malpighian tubules collect fluid, remove waste. waste travels to intestine
Insecta	labium, labrum hold food so mandible and maxillae can hold, tear, and cut. saliva moistens in mouth, stored in crop.	gizzard contains sharp chitinous plates to shred it, pass into stomach (midgut). gastric ceca mix food with digestive juices.	undigested food passes through hindgut (colon and rectum); Malpighian tubules in hindgut remove chemical waste. all waste leaves through anus
Chondrichthyes	specialized teeth to suit lifestyle	complete digestive tract	waste leaves through anus
Osteichthyes	usually carnivorous; jaws have teeth pointing inward. keep smaller fish, prey from escaping. tongue anchored, used to detect chemicals. mouth pharynx, esophagus.	stomach: digestion occurs in outlying ceca. liver and pancreas secrete digestive enzymes. intestine contains villi to increase surface area.	undigested food passes through anus. gills excrete nitrogenous waste. kidneys excrete nitrogenous waste, carried to urinary bladder.
Amphibia	tongue anchored in front; maxillary and vomerine teeth hold prey. alimentary canal complete: esophagus, stomach small intestine, large intestine. cloaca	gullet to stomach. glands secrete juices to break down food. nutrients absorbed into the blood stream in small intestine.	cloacal opening (hold waste from kidneys and bladder). carbon dioxide diffuses through skin. kidneys filter nitrogenous waste to produce urine.
Reptilia	may swallow whole; kill by injection or suffocation. jaws unhinge to allow mouth to open wide to swallow prey.	saliva begins digestion in esophagus, then in stomach	excrete uric acid to conserve water
Aves	no teeth or jaw bones. food passes from mouth to esophagus. crop stores and moistens food.	proventriculus of stomach secretes gastric fluids. gizzard crushes and grinds food. small intestine finishes breakdown, nutrients absorbed.	kidneys filter nitrogenous waste: form concentrated uric acid waste. ureters pass to cloaca.
Mammalia	specialized teeth. food enters mouth, begins digestion	stomach, intestine, accessory digestive glands	kidneys filter nitrogenous waste; undigested waste passes through anus.

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