#internal_organ__viscus  a main organ that is situated inside the body
  supertype:  organ  a fully differentiated structural and functional unit in an animal that is specialized for some particular function
  subtype:  viscera__entrail__innard  internal organs collectively (especially those in the abdominal cavity); "`viscera' is the plural form of `viscus'"
  subtype:  excretory_organ__excretoryorgan__urinary_organ__urinaryorgan  an organ that separates waste substances from the blood and discharges them
     subtype:  flame_cell__flamecell  organ of excretion in flatworms
     subtype:  kidney  either of two bean-shaped excretory organs that filter wastes (especially urea) from the blood and excrete them and water in urine; urine passes out of the kidney through ureters to the bladder
  subtype:  gallbladder  a muscular sac attached to the liver that secretes bile and stores it until needed for digestion
  subtype:  liver  large and complicated reddish-brown glandular organ located in the upper right portion of the abdominal cavity; secretes bile and functions in metabolism of protein and carbohydrate and fat; synthesizes substances involved in the clotting of the blood; synthesizes vitamin A; detoxifies poisonous substances and breaks down worn-out erythrocytes
  subtype:  heart.internal_organ__pump__ticker  the hollow muscular organ located behind the sternum and between the lungs; its rhythmic contractions pump blood through the body; "he stood still, his heart thumping wildly"
     subtype:  athlete's_heart  enlarged heart commonly found among athletes trained for endurance
     subtype:  biauriculate_heart  a heart (as of mammals and birds and reptiles) have two auricles
  subtype:  tummy__stomach__tum__breadbasket  an enlarged and muscular saclike organ of the alimentary canal; the principal organ of digestion
     subtype:  craw__crop  a pouch in many birds and some lower animals that resembles a stomach for storage and preliminary maceration of food
     subtype:  rumen__first_stomach__firststomach  the first compartment of the stomach of a ruminant; here food is collected and returned to the mouth as cud for chewing
     subtype:  second_stomach__reticulum  the second compartment of the stomach of a ruminant
     subtype:  psalterium__omasum__third_stomach__thirdstomach  the third compartment of the stomach of a ruminant
     subtype:  abomasum__fourth_stomach  the fourth compartment of the stomach of a ruminant; the one where digestion takes place
  subtype:  respiratory_organ__respiratoryorgan  any organ involved in the process of respiration
     subtype:  branchia__gill  respiratory organ of aquatic animals that breathe oxygen dissolved in water
        subtype:  ctenidium  comb-like respiratory structure serving as the gill of certain mollusks
        subtype:  ceras__cera  one of the often brightly colored and branching hornlike structures on the back of the nudibranch (and other related mollusks) that serve as gills
        subtype:  external_gill  occurs in some mollusks and in tadpoles and other immature amphibians
     subtype:  lung  either of two saclike respiratory organs in the chest of vertebrates; serves to remove carbon dioxide and provide oxygen to the blood
     subtype:  book_lung  organ in many arachnids containing many thin folds of membrane resembling the leaves of a book
  subtype:  intestine__bowel__gut  the part of the alimentary canal between the stomach and the anus
     subtype:  small_intestine__smallintestine  the longest part of the alimentary canal; where digestion is completed
        subtype:  duodenum  the part of the small intestine between the stomach and the jejunum
        subtype:  jejunum  the part of the small intestine between the duodenum and the ileum
        subtype:  ileum  the part of the small intestine between the jejunum and the cecum
     subtype:  large_intestine__largeintestine  beginning with the cecum and ending with the rectum; includes the cecum and the colon and the rectum; extracts moisture from food residues which are later excreted as feces
        subtype:  colon  the part of the large intestine between the cecum and the rectum; it extracts moisture from food residues before they are excreted
           subtype:  megacolon  an abnormal enlargement of the colon; can be congenital (as in Hirschsprung's disease) or acquired (as when children refuse to defecate)
           subtype:  transverse_colon  the part of the large intestine that extends across the abdominal cavity and joins the ascending to the descending colon
           subtype:  ascending_colon__ascendingcolon  the part of the large intestine that ascends from the cecum to the transverse colon
           subtype:  descending_colon  the part of the large intestine that descends from the transverse colon to the sigmoid colon
           subtype:  sigmoid_colon__sigmoidcolon__sigmoid_flexure__sigmoidflexure  the s-shaped curve between the descending colon and the rectum
  subtype:  hindgut  the caudal part of the alimentary canal in vertebrate embryos

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