Dissection
Human dissections were carried out by the Greek physicians Herophilus of Chalcedon and Erasistratus of Chios in the early part of the third century BC. During this period, the first exploration into full human anatomy was performed rather than a base knowledge gained from 'problem-solution' delving. While there was a deep taboo in Greek culture concerning human dissection, there was at the time a strong push by the Ptolemaic government to build Alexandria into a hub of scientific study. For a time, Roman law forbade dissection and autopsy of the human body, so physicians had to use other cadavers. Galen, for example, dissected the Barbary macaque and other primates, assuming their anatomy was basically the same as that of humans.
Cadaver
Galen (130–201 AD) connected the famous works of Aristotle and other Greek physicians to his understanding of the human body. Galenic anatomy and physiology were considered to be the most prominent methods to teach when dealing with the study of the human body during this time period.  Andreas Vesalius (1514-1564), known as the father of modern human anatomy, based his knowledge off of Galen's findings and his own dissection of human cadavers.  Vesalius performed multiple dissections on cadavers for medical students to recognize and understand how the interior body parts of a human being worked.  Cadavers also helped Vesalius discredit previous notions of work published by the Greek physician Galen dealing with certain functions of the brain and human body.  Vesalius concluded that Galen never did use cadavers in order to gain a proper understanding of human anatomy but instead used previous knowledge from his predecessors.