internal organ

internal organs collectively (especially those in the abdominal cavity)

an organ that separates waste substances from the blood and discharges them

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

the hollow muscular organ located behind the sternum and between the lungs; its rhythmic contractions move the blood through the body

an enlarged and muscular saclike organ of the alimentary canal; the principal organ of digestion

any organ involved in the process of respiration

the part of the alimentary canal between the stomach and the anus

the caudal part of the alimentary canal in vertebrate embryos

organ of excretion in flatworms

a pouch in many birds and some lower animals that resembles a stomach for storage and preliminary maceration of food

the first compartment of the stomach of a ruminant; here food is collected and returned to the mouth as cud for chewing

the second compartment of the stomach of a ruminant

the third compartment of the stomach of a ruminant

the fourth compartment of the stomach of a ruminant; the one where digestion takes place

respiratory organ of aquatic animals that breathe oxygen dissolved in water

either of two bean-shaped excretory organs that filter wastes (especially urea) from the blood and excrete them and water in urine

either of two saclike respiratory organs in the chest of vertebrates; serves to remove carbon dioxide and provide oxygen to the blood

enlarged heart commonly found among athletes trained for endurance

a heart (as of mammals and birds and reptiles) having two auricles

organ in many arachnids containing many thin folds of membrane resembling the leaves of a book

the longest part of the alimentary canal; where digestion is completed

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