Body & Health · Depth 2 · Introductory · 7 min read

Anatomy

How the human body is built: the language of anatomy, bones, muscles, skin, nerves, senses, heart, lungs, gut, kidneys, and how scans see inside.

This page is general education, not professional advice. For decisions about your health, safety, money or legal situation, consult a qualified professional.

Real-life examples

  • Which side is your thumb on?

    In the anatomical position the palms face forward, so the front of the hand is the palm and the thumb, being furthest from the body's midline, is called lateral.[3]

  • The lub-dub of a heartbeat

    The first heart sound comes as the mitral and tricuspid valves close at the start of each contraction, and the second as the aortic and pulmonary valves close at its end; each closure stops blood flowing backwards.[2, 21, 20]

  • Why crying makes your nose run

    Tears from the lacrimal gland wash over the eye, drain through tiny openings into a sac and then down the nasolacrimal duct, which empties into the nose.[8]

  • One throat for air and food

    The pharynx is shared by the respiratory and digestive systems, so air and swallowed food pass through the same space.[9, 32]

Connected across the map

Evidence & sources

Level 2 · Authoritative

Supported by highly reputable institutions such as government agencies, universities or standards bodies.

Why this level? The basic structure of the human body is long established. The organ systems (skeleton, muscles, nerves, heart and blood vessels, lungs, gut, kidneys and reproductive organs) are each drawn from two institutions: the Human Anatomy Lab Manual published by Mavs Open Press at the University of Texas at Arlington and the anatomy training modules of the US National Cancer Institute's SEER program. The heart also draws on the CDC (US) and the Applied Human Anatomy manual of Virginia Tech Carilion School of Medicine, and MedlinePlus (US National Library of Medicine) gives the definition and the CT and MRI section. Some parts still rest on one source: the skin, the special senses and the anatomical position on the UTA lab manual, and the body cavities on the SEER modules. The page keeps to named structures and plain functions and leaves out the lab manual's estimated figures. It does not cover named muscles and nerves, the endocrine, lymphatic and immune organs, the heart's fine structure and electrical system, development, ageing or any disease or treatment. This page explains; it is not medical advice.

This is a Knowledge Atlas editorial classification of the sources we could find, not a certificate of truth. How we evaluate knowledge

Sources

Based on 37 sources from 5 institutions: MedlinePlus, Virginia Tech, Mavs Open Press (UTA), CDC, NCI SEER Training.

Show all 37 sourcesHide the list
  1. AuthoritativeMedlinePlus (U.S. National Library of Medicine)· Government agencyAnatomyOpened and checked against this page on 30 Sept 2026
  2. ScholarlyVirginia Tech (Carilion School of Medicine and Virginia Tech Publishing)· UniversityApplied Human Anatomy (Nolan and McNamara, Virginia Tech Carilion School of Medicine, 2022; CC BY 4.0)Opened and checked against this page on 30 Sept 2026
  3. ScholarlyMavs Open Press, University of Texas at Arlington Libraries· University1.1: Lab 1- Anatomical LanguageOpened and checked against this page on 1 Oct 2026
  4. ScholarlyMavs Open Press, University of Texas at Arlington Libraries· University2.1: Lab 2- Bones and Bone MarkingsOpened and checked against this page on 1 Oct 2026
  5. ScholarlyMavs Open Press, University of Texas at Arlington Libraries· University10.1: Lab 10- The Muscular and Integumentary systemsOpened and checked against this page on 1 Oct 2026
  6. ScholarlyMavs Open Press, University of Texas at Arlington Libraries· University3.1: Lab 3- Spinal Cord and Spinal NervesOpened and checked against this page on 1 Oct 2026
  7. ScholarlyMavs Open Press, University of Texas at Arlington Libraries· University4.1: Lab 4- Brain and Cranial NervesOpened and checked against this page on 1 Oct 2026
  8. ScholarlyMavs Open Press, University of Texas at Arlington Libraries· University5.1: Lab 5- Special SensesOpened and checked against this page on 1 Oct 2026
  9. ScholarlyMavs Open Press, University of Texas at Arlington Libraries· University6.1: Lab 6- Respiratory SystemOpened and checked against this page on 1 Oct 2026
  10. ScholarlyMavs Open Press, University of Texas at Arlington Libraries· University7.1: Lab 7- The Cardiovascular systemOpened and checked against this page on 1 Oct 2026
  11. ScholarlyMavs Open Press, University of Texas at Arlington Libraries· University8.1: Lab 8- Digestive SystemOpened and checked against this page on 1 Oct 2026
  12. ScholarlyMavs Open Press, University of Texas at Arlington Libraries· University9.1: Lab 9- Urinary and Reproductive SystemsOpened and checked against this page on 1 Oct 2026
  13. AuthoritativeCenters for Disease Control and Prevention· Government agencyHow the Heart WorksOpened and checked against this page on 30 Sept 2026
  14. AuthoritativeMedlinePlus (U.S. National Library of Medicine)· Government agencyCT ScansOpened and checked against this page on 30 Sept 2026
  15. AuthoritativeMedlinePlus (U.S. National Library of Medicine)· Government agencyMRI ScansOpened and checked against this page on 30 Sept 2026
  16. AuthoritativeMedlinePlus (U.S. National Library of Medicine)· Government agencyLymphatic DiseasesOpened and checked against this page on 30 Sept 2026
  17. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyAnatomical Terminology | SEER TrainingOpened and checked against this page on 1 Oct 2026
  18. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyClassification & Structure of Blood VesselsOpened and checked against this page on 1 Oct 2026
  19. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyCirculatory Pathways | SEER TrainingOpened and checked against this page on 1 Oct 2026
  20. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyPhysiology of the Heart | SEER TrainingOpened and checked against this page on 1 Oct 2026
  21. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyStructure of the Heart | SEER TrainingOpened and checked against this page on 1 Oct 2026
  22. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyIntroduction to the Digestive SystemOpened and checked against this page on 1 Oct 2026
  23. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyAccessory Organs | SEER TrainingOpened and checked against this page on 1 Oct 2026
  24. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyGeneral Structure of the Digestive SystemOpened and checked against this page on 1 Oct 2026
  25. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyMuscle Types | SEER TrainingOpened and checked against this page on 1 Oct 2026
  26. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyThe Central Nervous System | SEER TrainingOpened and checked against this page on 1 Oct 2026
  27. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyThe Peripheral Nervous System | SEER TrainingOpened and checked against this page on 1 Oct 2026
  28. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyIntroduction to the Reproductive SystemOpened and checked against this page on 1 Oct 2026
  29. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyTestes | SEER TrainingOpened and checked against this page on 1 Oct 2026
  30. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyBronchi, Bronchial Tree, & LungsOpened and checked against this page on 1 Oct 2026
  31. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyLarynx & Trachea | SEER TrainingOpened and checked against this page on 1 Oct 2026
  32. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyPharynx | SEER TrainingOpened and checked against this page on 1 Oct 2026
  33. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyIntroduction to the Skeletal SystemOpened and checked against this page on 1 Oct 2026
  34. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyStructure of Bone Tissue | SEER TrainingOpened and checked against this page on 1 Oct 2026
  35. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyUrinary Bladder | SEER TrainingOpened and checked against this page on 1 Oct 2026
  36. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyKidneys | SEER TrainingOpened and checked against this page on 1 Oct 2026
  37. AuthoritativeNational Cancer Institute, SEER Training Modules (Anatomy & Physiology)· Government agencyUrethra | SEER TrainingOpened and checked against this page on 1 Oct 2026