Siseelundeid

Siseelundeid (internal organs) refer to the organs contained within the body's cavities, primarily in the thoracic and abdominal regions, including the heart, lungs, liver, stomach, intestines, kidneys, bladder, pancreas, spleen, and the reproductive glands. Together they perform the essential processes of circulation, respiration, digestion, excretion, reproduction, and hormonal regulation.

Most siseelundeid are suspended inside body cavities by membranes and connective tissue. They are grouped into organ systems such as the circulatory, respiratory, digestive, urinary, endocrine, and reproductive systems, and many are paired (for example, kidneys and lungs) while others are single (for example, the liver).

During embryonic development, siseelundeid arise from the three germ layers and differentiate into specialized tissues. Variations include congenital anomalies, size differences, and sometimes organ absence or duplications.

Health concerns related to siseelundeid include infections, inflammation, tumors, metabolic and degenerative diseases, and organ failure. Diagnosis relies on imaging techniques (such as ultrasound, CT, and MRI) and laboratory tests, while treatment may involve medication, surgery, or organ transplantation in select cases. The study of siseelundeid is central to fields such as anatomy, physiology, and clinical medicine, and it informs both basic research and medical practice.