List of systems of the human body

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. ^[1]

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 system	Description	Component organs
Respiratory system	breathing; exchange of oxygen and carbon dioxide	nose, mouth, paranasal sinuses, pharynx, larynx, trachea, bronchi, lungs and thoracic diaphragm
Digestive and excretory system	digestion; breakdown and absorption of nutrients, excretion of solid wastes	teeth, tongue, salivary glands, esophagus, stomach, liver, gallbladder, pancreas, small intestine, large intestine, rectum and anus
Circulatory system	circulate blood in order to transport nutrients, waste, hormones, O2, CO2, and aid in maintaining pH and temperature	blood, heart, arteries, veins and capillaries
Urinary system	maintain fluid and electrolyte balance, purify blood and excrete liquid waste (urine)	kidneys, ureters, bladder and urethra
Integumentary system	exterior protection of body and thermal regulation	skin, hair, fat and nails
Skeletal system	structural support and protection, production of blood cells	bones, cartilage, ligaments and tendons
Muscular system	movement of body, production of heat	skeletal muscles, smooth muscles and cardiac muscle
Endocrine system	communication within the body using hormones made by endocrine glands	hypothalamus, pituitary, pineal gland, thyroid, parathyroid and adrenal glands, ovaries and testicles
Exocrine system	various functions including lubrication and protection	ceruminous glands, lacrimal glands, sebaceous glands and mucus
Lymphatic system	return lymph to the bloodstream, aid immune responses, form white blood cells	lymph, lymph nodes, lymph vessels, tonsils, spleen and thymus
Nervous system	sensing and processing information, controlling body activities	brain, spinal cord, nerves, sensory organs
Reproductive system	sex organs involved in reproduction	ovaries, fallopian tubes, uterus, vagina, vulva, penis, testicles, vasa deferentia, seminal vesicles and prostate

• Clockwise from top left: integumentary system
• skeletal system
• nervous system
• cardiovascular system
• endocrine system
• muscular system

• Clockwise from top left: lymphatic system
• respiratory system
• urinary system
• female reproductive system
• male reproductive system
• digestive system

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

1. Betts, J Gordon; et al. (2013). "Structural Organization of the Human Body". Anatomy and Physiology. OpenStax. ISBN   978-1-947172-04-3. Archived from the original on 2023-03-24. Retrieved 4 June 2025.