Human Body Organs and Systems
ORGANS: Several kinds of tissues combine together to form an ORGAN. For instance, stomach is an organ that is composed of nerve tissue, muscle tissue, and glandular epithelial tissue. VISCERA (singular: viscus) are internal organs. Abdominal viscera are the liver, stomach, large and small intestines, pancreas, spleen, and gallbladder. SYSTEMS: Groups of organs combine together to form a SYSTEM. Each system performs complex functions. For instance, respiratory system consists of NOSE, PHARYNX, LARYNX (VOICE BOX), TRACHEA (WINDPIPE), BRONCHIAL TUBES, AND LUNGS. Now we can see each system and its organs: 1. DIGESTIVE SYSTEM: This system contains mouth, pharynx (throat), esophagus, stomach, intestines (small and large intestines), liver, gallbladder, and pancreas. 2. URINARY AND EXCRETORY SYSTEM: This systems consists of kidneys, ureters (from these tubes urine comes out of the kidneys to urinary bladder), urinary bladder, urethra (from this opening urine comes out