This is a list of the main systems of the human body, including organ systems. An organ system is a group of organs that work together to perform major functions or meet physiological needs of the body.
Major organ systems There are 11 to 12 distinct organ systems. The endocrine and exocrine systems are sometimes referred to jointly as the endocrine system. Organ systemDescriptionComponent organsRespiratory systembreathing; exchange of oxygen and carbon dioxidenose, mouth, paranasal sinuses, pharynx, larynx, trachea, bronchi, lungs and thoracic diaphragmDigestive and excretory systemdigestion; breakdown and absorption of nutrients, excretion of solid wastesteeth, tongue, salivary glands, esophagus, stomach, liver, gallbladder, pancreas, small intestine, large intestine, rectum and anusCirculatory systemcirculate blood in order to transport nutrients, waste, hormones, O2, CO2, and aid in maintaining pH and temperatureblood, heart, arteries, veins and capillariesUrinary systemmaintain fluid and electrolyte balance, purify blood and excrete liquid waste (urine)kidneys, ureters, bladder and urethraIntegumentary systemexterior protection of body and thermal regulationskin, hair, fat and nailsSkeletal systemstructural support and protection, production of blood cellsbones, cartilage, ligaments and tendonsMuscular systemmovement of body, production of heatskeletal muscles, smooth muscles and cardiac muscleEndocrine systemcommunication within the body using hormones made by endocrine glandshypothalamus, pituitary, pineal gland, thyroid, parathyroid and adrenal glands, ovaries and testiclesExocrine systemvarious functions including lubrication and protectionceruminous glands, lacrimal glands, sebaceous glands and mucusLymphatic systemreturn lymph to the bloodstream, aid immune responses, form white blood cellslymph, lymph nodes, lymph vessels, tonsils, spleen and thymusNervous systemsensing and processing information, controlling body activitiesbrain, spinal cord, nerves, sensory organs Reproductive systemsex organs involved in reproductionovaries, fallopian tubes, uterus, vagina, vulva, penis, testicles, vasa deferentia, seminal vesicles and prostate
Organ sub-systems
Cardiovascular
Cardiac conduction system
Lymphatic
Glymphatic system
Nervous
Central nervous system Peripheral nervous system Autonomic nervous system Sympathetic nervous system Parasympathetic nervous system Enteric nervous system Somatic nervous system Sensory nervous system Somatosensory system Visual system Olfactory system Gustatory system Auditory system Vestibular system
Reproductive
Female reproductive system Male reproductive system
Other systems
Genitourinary system Haematopoietic system Immune system Innate immune system Adaptive immune system Mononuclear phagocyte system Reticuloendothelial system Musculoskeletal system Neuroendocrine system
See also List of distinct cell types in the adult human body List of organs of the human body
References