Human anatomy
Every organ page answers the same questions: where it is, what it is made of, what supplies it, what it does, what goes wrong and how that is investigated and treated. Most are built on the 2,299-piece 3D atlas, so you can open the real shapes; the female reproductive organs, the breasts and the anatomy of gender-affirming surgery, which the atlas's adult male reference body does not model, show the modelled structures around them instead. Each links into physiology, symptoms, conditions, tests, imaging, procedures and medications.
Start here: full anatomy articles
Brain
The brain is about 1.4 kg of nervous tissue floating in cerebrospinal fluid inside the skull. Its wrinkled cerebral hemispheres handle perception,…
Lungs
The lungs are two spongy, cone-shaped organs filling most of the chest on either side of the heart. Air reaches them through a branching tree of…
Heart
The heart is a fist-sized muscular pump in the middle of the chest, tilted so that two-thirds of it lies to the left of the midline. Its four…
Coronary vessels
The coronary arteries are the heart's own blood supply: two vessels a few millimetres wide that arise from the aorta just above the aortic valve and…
Aorta
The aorta is the largest artery in the body, a thick elastic tube about 2.5-3 cm wide that carries every drop of oxygenated blood from the left…
Pelvic floor
The pelvic floor is a funnel-shaped sheet of skeletal muscle, mainly the levator ani and coccygeus on each side, that closes the lower opening of the…
Stomach
The stomach is a muscular, J-shaped bag in the upper left abdomen that receives food from the oesophagus, churns it with acid and enzymes into a…
Large intestine
The large intestine is the last 1.5 metres of the gut: the caecum with its appendix, the ascending, transverse, descending and sigmoid colon, the…
Liver
The liver is the largest internal organ, about 1.5 kg of chemical factory tucked under the right ribs. It receives nutrient-rich blood from the gut…
Pancreas
The pancreas is a soft, elongated gland about 15 cm long lying across the back of the upper abdomen behind the stomach. It is two organs in one:…
Kidneys
The two kidneys are bean-shaped organs the size of a fist, lying against the back wall of the abdomen on either side of the spine. Each contains…
Uterus & cervix
The uterus is a hollow, thick-walled, pear-shaped muscular organ about 7.5 cm long that lies in the pelvis between the bladder and the rectum. Its…
Ovaries & fallopian tubes
The ovaries are two almond-shaped glands about 3 cm long that lie against the side walls of the pelvis. Each holds a lifetime's supply of eggs,…
Vagina
The vagina is a fibromuscular canal about 8 to 10 cm long that runs upwards and backwards from the vulva to the cervix, lying between the bladder and…
Vulva & clitoris
The vulva is the external genitalia: the mons pubis, the labia majora and minora, the clitoris, the vestibule into which the urethra and vagina open,…
Breasts
The breasts are paired modified sweat glands on the front of the chest wall, lying over the pectoralis major muscles and made of milk-producing lobes…
Neovagina
A neovagina is a vaginal canal and vulva constructed by vaginoplasty, most often as gender-affirming surgery for trans women and some non-binary…
Neophallus
A neophallus is a penis constructed by surgery, most often as gender-affirming surgery for trans men and some non-binary people, and also after loss…
Vertebral column
The vertebral column is a stack of 33 vertebrae, 24 of them movable, separated by shock-absorbing discs and bound by ligaments and muscles. It…
Knee joint
The knee is the largest joint in the body: a hinge between the femur and tibia, with the patella gliding in front, held together by four main…
Explore by body system
Each system page lists every modelled structure with an overview, functions and clinical notes.
Explore by region
Skeleton
Skull
22 bones forming the cranium that protects the brain and the facial skeleton.
Vertebral column
The vertebral column is a stack of 33 vertebrae, 24 of them movable, separated by shock-absorbing discs and bound by ligaments and muscles. It…
Rib cage
Twelve pairs of ribs, their costal cartilages and the sternum protect the heart and lungs and move with breathing.
Bony pelvis
The two hip bones with the sacrum and coccyx transfer body weight to the legs and protect pelvic organs.
Shoulder girdle
Clavicle and scapula link each arm to the trunk.
Hand skeleton
27 bones per hand: 8 carpals, 5 metacarpals and 14 phalanges.
Foot skeleton
26 bones per foot: 7 tarsals, 5 metatarsals and 14 phalanges.
Knee joint
The knee is the largest joint in the body: a hinge between the femur and tibia, with the patella gliding in front, held together by four main…
Muscles
Diaphragm
The dome-shaped muscle separating chest from abdomen; the main muscle of breathing.
Pelvic floor
The pelvic floor is a funnel-shaped sheet of skeletal muscle, mainly the levator ani and coccygeus on each side, that closes the lower opening of the…
Heart
Arteries
Coronary vessels
The coronary arteries are the heart's own blood supply: two vessels a few millimetres wide that arise from the aorta just above the aortic valve and…
Aorta
The aorta is the largest artery in the body, a thick elastic tube about 2.5-3 cm wide that carries every drop of oxygenated blood from the left…
Nervous system
Brain
The brain is about 1.4 kg of nervous tissue floating in cerebrospinal fluid inside the skull. Its wrinkled cerebral hemispheres handle perception,…
Cerebellum
The 'little brain' behind the brainstem coordinates balance, posture and the timing of movements.
Brainstem
Midbrain, pons and medulla connect the brain to the spinal cord and run breathing, heart rate and consciousness.
Sensory organs
Eye
The eyeball and its parts: cornea, lens, iris, retina and the tissues that protect and move it.
Ear
The external ear gathers sound; the middle and inner ear (not modelled here) convert it to nerve signals and sense balance.
Respiratory
Nose
Nasal bones and cartilages shape the nose; the conchae inside warm and filter the air.
Larynx
The voice box: a cartilage frame with the vocal ligaments, guarding the airway and producing sound.
Trachea & bronchial tree
The windpipe and the branching airways that carry air into every segment of the lungs.
Lungs
The lungs are two spongy, cone-shaped organs filling most of the chest on either side of the heart. Air reaches them through a branching tree of…
Digestive
Tongue
A muscular organ for taste, chewing, swallowing and speech.
Oesophagus
A muscular tube carrying swallowed food from the pharynx to the stomach.
Stomach
The stomach is a muscular, J-shaped bag in the upper left abdomen that receives food from the oesophagus, churns it with acid and enzymes into a…
Small intestine
Duodenum, jejunum and ileum: about six metres where most digestion and absorption happens.
Large intestine
The large intestine is the last 1.5 metres of the gut: the caecum with its appendix, the ascending, transverse, descending and sigmoid colon, the…
Liver
The liver is the largest internal organ, about 1.5 kg of chemical factory tucked under the right ribs. It receives nutrient-rich blood from the gut…
Gallbladder & bile ducts
Stores and concentrates bile, releasing it into the duodenum through the cystic and common bile ducts.
Pancreas
The pancreas is a soft, elongated gland about 15 cm long lying across the back of the upper abdomen behind the stomach. It is two organs in one:…
Urinary
Kidneys
The two kidneys are bean-shaped organs the size of a fist, lying against the back wall of the abdomen on either side of the spine. Each contains…
Urinary bladder & urethra
The bladder stores urine; the urethra carries it out of the body.
Ureters
Muscular tubes carrying urine from the kidneys to the bladder.
Reproductive
Prostate
A walnut-sized gland below the bladder that adds fluid to semen.
Testes & epididymis
The testes produce sperm and testosterone; the epididymis stores maturing sperm.
Penis
Erectile bodies (corpora cavernosa and spongiosum) and the glans.
Endocrine
Adrenal glands
Glands on top of each kidney producing cortisol, aldosterone and adrenaline.
Pituitary gland
The master gland at the base of the brain, controlling growth, thyroid, adrenal and reproductive hormones.
Lymphatic & immune
Spleen
Filters blood, recycles red cells and houses immune cells.
Thymus
Behind the sternum; trains T lymphocytes in childhood and shrinks with age.
Female reproductive
Uterus & cervix
The uterus is a hollow, thick-walled, pear-shaped muscular organ about 7.5 cm long that lies in the pelvis between the bladder and the rectum. Its…
Ovaries & fallopian tubes
The ovaries are two almond-shaped glands about 3 cm long that lie against the side walls of the pelvis. Each holds a lifetime's supply of eggs,…
Vagina
The vagina is a fibromuscular canal about 8 to 10 cm long that runs upwards and backwards from the vulva to the cervix, lying between the bladder and…
Ligaments of the uterus & ovary
The peritoneal folds and fibromuscular bands that suspend the uterus, tubes and ovaries: the broad ligament with its mesosalpinx and mesovarium, the round, cardinal and uterosacral ligaments, the suspensory and ovarian ligaments and the vesico-uterine pouch.
Vulva & clitoris
The vulva is the external genitalia: the mons pubis, the labia majora and minora, the clitoris, the vestibule into which the urethra and vagina open,…
Breasts
The breasts are paired modified sweat glands on the front of the chest wall, lying over the pectoralis major muscles and made of milk-producing lobes…