The tricuspid valve of the heart and its function is documented in the treatise On the Heart. The texts show an understanding of musculoskeletal structure, and the beginnings of understanding of the function of certain organs, such as the kidneys. Many medical texts by various authors are collected in the Hippocratic Corpus, none of which can definitely be ascribed to Hippocrates himself. Another important philosopher at the time was Empedocles, who viewed blood as the innate heat and argued that the heart was the chief organ of the body and the source of pneuma (this could refer to either breath or soul), which was distributed by the blood vessels. Ancient physicians such as Acron, Pausanias, and Philistion of Locri may had also conducted anatomical investigations. In the fifth-century BCE, the philosopher Alcmaeon may have been one of the first to have dissected animals for anatomical purposes, and possibly identified the optic nerves and Eustachian tubes. Much of the nomenclature, methods, and applications for the study of anatomy can be traced back to the works of the ancient Greeks. However, they did not have a theory as to where saliva and sweat came from. The Egyptians seem to have known little about the function of the kidneys and the brain and made the heart the meeting point of a number of vessels which carried all the fluids of the body вЂ“ blood, tears, urine and semen.

It notes that the heart is the center of blood supply, and attached to it are vessels for every member of the body. 1550 BC) features a treatise on the heart. Other vessels are described, some carrying air, some mucus, and two to the right ear are said to carry the 'breath of life', while two to the left ear the 'breath of death'. This treatise shows that the heart, its vessels, liver, spleen, kidneys, hypothalamus, uterus and bladder were recognized, and that the blood vessels were known to emanate from the heart. The study of anatomy begins at least as early as 1600 BC, the date of the Edwin Smith Surgical Papyrus.

Hieroglyph designating the brain or skull in the Edwin Smith papyrus. An understanding of the structures and functions of organs in the body has been an integral part of medical practice and a source for scientific investigations ever since. Important anatomical work was carried out by Mondino de Luzzi, Berengario da Carpi, and Jacques Dubois, culminating in Andreas Vesalius's seminal work De Humani Corporis Fabrica (1543). The Renaissance brought a reconsideration of classical medical texts, and anatomical dissections became once again fashionable for the first time since Galen. The development of the study of anatomy gradually built upon concepts that were present in Galen's work, which was a part of the traditional medical curriculum in the Middle Ages. Anatomical knowledge in antiquity would reach its apex in the person of Galen, who made important discoveries through his medical practice and his dissections of monkeys, oxen, and other animals. During the Hellenistic Age, dissection and vivesection of human beings took place for the first time in the work of Herophilos and Erasistratus. Aristotle advocated dissection of animals as part of his program for understanding the causes of biological forms. Ancient Greek philosophers, like Alcmaeon and Empedocles, and ancient Greek doctors, like Hipprocrates and his school, paid attention to the causes of life, disease, and different functions of the body. Theoretical considerations of the structure and function of the human body did not develop until far later, in Ancient Greece. Written descriptions of human organs and parts can be traced back thousands of years to ancient Egyptian papyri, where attention to the body was necessitated by their highly elaborate burial practices. The history of anatomy extends from the earliest examinations of sacrificial victims to the sophisticated analyses of the body performed by modern anatomists and scientists. Dissection of a cadaver, 15th-century painting

Modern human anatomy program asuths