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HISTORY OF ANATOMY BY: HARITH RIYADH
THE HISTORY OF ANATOMY extends from the earliest examinations of sacrificial victims to the sophisticated analyses of the body performed by modern scientists. It has been characterized, over time, by a continually developing understanding of the functions of organs and structures in the body. Human anatomy was the most prominent of the biological sciences of the 19th and early 20th centuries. Methods have also improved dramatically.
EGYPTMain article: Ancient Egyptian anatomical studiesThe study of anatomy begins at least as early as 1600 BC, the date of the Edwin Smith Surgical Papyrus. 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. Other vessels are described, some carrying air, some mucus, and two to the right ear are said to carry the "breath of life",[clarification needed] while two to the left ear the "breath of death".[citation needed]The Ebers Papyrus (c. 1550 BC) features a treatise on the heart. It notes that the heart is the center of blood supply, and attached to it are vessels for every member of the body.
COThe Egyptians seem to have known little about the function of the kidneys and made the heart the meeting point of a number of vessels which carried all the fluids of the body – blood, tears, urine and semen. However, they did not have a theory as to where saliva and sweat came from
THE BIRTH OF BIOLOGY: 5TH - 4TH CENTURY BC The Greek philosophers, voracious in their curiosity, look with interest at the range of living creatures, from the humblest plant to man himself. A Greek name is coined by a German naturalist in the early 19th century for this study of all physical aspects of natural life - biology, from bios (life) and logos (word or discourse). It is a subject with clear subdivisions, such as botany, zoology or anatomy. But all are concerned with living organisms.The first man to make a significant contribution in biology is Alcmaeon, living in Crotona in the 5th century. Crotona is famous at the time for its Pythagorean scholars, but Alcmaeon seems not to have been of their school.
Alcmaeon is the first scientist known to have practised dissection in his researches. His aim is not anatomical, for his interest lies in trying to find the whereabouts of human intelligence. But in the course of his researches he makes the first scientific discoveries in the field of anatomy.The subsequent Greek theory, subscribed to even by Aristotle, is that the heart is the seat of intelligence. Alcmaeon reasons that since a blow to the head can affect the mind, in concussion, this must be where reason lies. In dissecting corpses to pursue this idea, he observes passages linking the brain with the eyes (the optic nerves) and the back of the mouth with the ears (Eustachian tubes).
HUMAN VIVISECTION: C.300 BC Early in the 3rd century BC two surgeons in Alexandria, Herophilus and Erasistratus, make the first scientific studies designed to discover the workings of human anatomy. The cost of their contribution to science would be considered too high in modern times (they acquire much of their information from Human vivisection, the patients being convicted criminals). But Celsus, a Roman writer on medical history, energetically justifies the suffering of the criminals as providing 'remedies for innocent people of all future ages'.
THE INFLUENTIAL ERRORS OF GALEN:
2nd century ADThe newly appointed chief physician to the gladiators in Pergamum, in AD 158, is a native of the city. He is a Greek doctor by the name of Galen. The appointment gives him the opportunity to study wounds of all kinds. His knowledge of muscles enables him to warn his patients of the likely outcome of certain operations - a wise precaution recommended in Galen's Advice to doctors.
But it is Galen's dissection of apes and pigs which give him the detailed information for his medical tracts on the organs of the body. Nearly 100 of these tracts survive. They become the basis of Galen's great reputation in medieval medicine, unchallenged until the anatomical work of Vesalius. Through his experiments Galen is able to overturn many long-held beliefs, such as the theory (first proposed by the Hippocratic school in about 400 BC, and maintained even by the physicians of Alexandria) that the arteries contain air - carrying it to all parts of the body from the heart and the lungs. This belief is based originally on the arteries of dead animals, which appear to be empty.
Galen is able to demonstrate that living arteries contain blood. His error, which will become the established medical orthodoxy for centuries, is to assume that the blood goes back and forth from the heart in an ebb-and-flow motion. This theory holds sway in medical circles until the time of Harvey.
SCIENCE'S SIESTA: 8TH - 15TH CENTURY In the profoundly Christian centuries of the European Middle Ages the prevailing mood is not conducive to scientific enquiry. God knows best, and so He should - since He created everything. Where practical knowledge is required, there are ancient authorities whose conclusions are accepted without question - Ptolemy in the field of astronomy, Galen on matters anatomical. A few untypical scholars show an interest in scientific research. The 13th-century Franciscan friar Roger Bacon is the most often quoted example, but his studies include alchemy and astrology as well as optics and astronomy. The practical scepticism required for science must await the Renaissance.
16TH CENTURY CONTRIBUTIONS
Began to compile extensive drawings of dissections of executed cadavers
Discovered the physiology of circulatory system The Anatomy Lesson of
Dr. Nicolaes Tulp, by Rembrandt, 1632
Dissection of a cadaver, 15th century painting
17TH AND 18TH CENTURIES
Few dissections were allowed
Only certain scientists were allowed to perform them
Tickets were sold to others wishing to see and draw the dissected bodies.
Doctors literally traveled from dissection to dissection The Anatomy Lesson of Dr.
Nicolaes Tulp, by Rembrandt, 1632
19TH CENTURY Began studying developmental anatomyEngland became the center of anatomical researchAnatomy Act of 1832 provided adequate supply of corpsesGray’s Anatomy first published 1858 (for traveling doctors)
MODERN ANATOMYUse of new technology provided further understanding of both structure and function of organs and organ systems
CAT scans, X-rays, Genetic tests, MRI
FUTURE OF ANATOMYHealth related studies are now centered around molecular biologyLooking for genetic and molecular indicators of disease New assays conducted more in vitro vs. in vivo
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