In some of its facets human anatomy is closely related to embryology, comparative anatomy and comparative embryology, through common roots in evolution; for example, much of the human body maintains the ancient segmental pattern that is present in all vertebrates with basic units being repeated, which is particularly obvious in the vertebral column and in the ribcage, and can be traced from very early embryos.

The human body consists of biological systems, that consist of organs, that consist of tissues, that consist of cells and connective tissue.

The history of anatomy has been characterized, over time, by a continually developing understanding of the functions of organs and structures in the body. Methods have also advanced dramatically, advancing from examination of animals through dissection of preserved cadavers (dead human bodies) to technologically complex techniques developed in the 20th century.

Study

Human anatomy, physiology and, biochemistry are complementary basic medical sciences, which are generally taught to medical students in their first year at medical school. Human anatomy can be taught regionally or systemically; that is, respectively, studying anatomy by bodily regions such as the head and chest, or studying by specific systems, such as the nervous or respiratory systems. The major anatomy textbook, Gray's Anatomy, has recently been reorganized from a systems format to a regional format,

Regional groups

• Head and neck — includes everything above the thoracic inlet
• Upper limb — includes the hand, wrist, forearm, elbow, arm, and shoulder.
• Thorax — the region of the chest from the thoracic inlet to the thoracic diaphragm.
• Human abdomen to the pelvic brim or to the pelvic inlet.
• The back — the spine and its components, the vertebrae, sacrum, coccyx, and intervertebral disks .
• Pelvis and Perineum — the pelvis consists of everything from the pelvic inlet to the pelvic diaphragm. The perineum is the region between the sex organs and the anus.
• Lower limb — everything below the inguinal ligament, including the hip, the thigh, the knee, the leg, the ankle, and the foot.

Major organ systems

• Circulatory system: pumping and channeling blood to and from the body and lungs with heart, blood, and blood vessels.
• Digestive system: digestion and processing food with salivary glands, esophagus, stomach, liver, gallbladder, pancreas, intestines, rectum, and anus.
• Endocrine system: communication within the body using hormones made by endocrine glands such as the hypothalamus, pituitary or pituitary gland, pineal body or pineal gland, thyroid, parathyroids, and adrenals or adrenal glands
• Immune system: protecting against disease by identifying and killing pathogens and tumor cells.
• Integumentary system: skin, hair and nails
• Lymphatic system: structures involved in the transfer of lymph between tissues and the blood stream, the lymph and the nodes and vessels that transport it including the Immune system: defending against disease-causing agents with leukocytes, tonsils, adenoids, thymus, and spleen
• Activity system: movement with muscles and human skeleton (structural support and protection with bones, cartilage, ligaments, and tendons).
• Nervous system: collecting, transferring and processing information with brain, spinal cord, peripheral nerves, and nerves
• Reproductive system: the sex organs, such as ovaries, fallopian tubes, uterus, vagina, mammary glands, testes, vas deferens, seminal vesicles, prostate, and penis.
• Respiratory system: the organs used for breathing, the pharynx, larynx, trachea, bronchi, lungs, and diaphragm.
• Urinary system: kidneys, ureters, bladder and urethra involved in fluid balance, electrolyte balance and excretion of urine.