Visceral organ are large bodily organs located within the cavities of the torso. They are also known collectively as the viscera and are located within three major body cavities: the chest, the abdomen and the pelvis. The cavities in the chest and pelvis have special names, called thoracic and cervical.
The visceral organs of the thorax are protected by the ribs and sternum. They include the heart, which is centrally located high in the chest and slightly to the left, and the lungs, which are located behind the heart and almost fill the ribcage from left to right. Underneath the lungs is a sheet of muscle called the diaphragm, which divides the chest from the abdomen and forces air in and out of the lungs. Higher up, above the ribs, are the thyroid gland and the trachea. They are only partially protected via cartilage in the neck.
The visceral organs of the abdomen include the stomach, the large and small intestines, the pancreas, the kidneys, the appendix, the adrenal gland, the gall bladder, the liver, the spleen and the peritoneum. The peritoneum is a membrane that surrounds the other organs and provides them with structural support within the abdomen via the secretion of a liquid called serous fluid. Many of these organs are specialized for the digestion of food. No protective bone is present in the abdomen, although strong muscles and fat storage in this area does provide a buffer between these organs and the outside world.
The visceral organs of the cervix are protected by the pelvic bone, and many are specialized for reproduction or excretion of waste. They include the bladder, the ovaries and testicles, the uterus, and the rectum. Testicles are located within the pelvis at birth, until they descend into the scrotum at puberty.