Blood supply to the brain is incredibly important. Think of it as plugging in your laptop—you need a continuous power source to keep it running (so you can reblog hundreds of gifsets of kittens).
To read more about the brain, read our latest blog post here!
Dissection of the neck, shoulder and axilla.
By Joseph Maclise
Dissection of the neck, shoulder and axilla, deep dissection, shown in 2 numbered illustrations. 1 illustration showing thoracic and shoulder muscles divided to show brachiocephalic vein, axillary artery, brachial plexus, and axillary lymph nodes. Male cadaver, in vivo, anterior view. 1 illustration of dissection of axilla shown in isolation, showing brachiocephalic veins, axillary artery and axillary lymph nodes. Anterior view.
General: Plate signed with the artist’s monogram JM [Joseph Maclise]; printed by M. & N. Hanhart.
The earliest known writings on the circulatory system are found in the Ebers Papyrus (16th century BCE), an ancient Egyptian medical papyrus containing over 700 prescriptions and remedies, both physical and spiritual. In the papyrus, it acknowledges the connection of the heart to the arteries. The Egyptians thought air came in through the mouth and into the lungs and heart. From the heart, the air traveled to every member through the arteries. Although this concept of the circulatory system is greatly flawed, it represents one of the earliest accounts of scientific thought.
In the 6th century BCE, the knowledge of circulation of vital fluids through the body was known to the Ayurvedic physician Sushruta in ancient India. He also seems to have possessed knowledge of the arteries, described as ‘channels’ by Dwivedi & Dwivedi (2007). The valves of the heart were discovered by a physician of the Hippocratean school around the 4th century BCE. However their function was not properly understood then. Because blood pools in the veins after death, arteries look empty. Ancient anatomists assumed they were filled with air and that they were for transport of air.
The Greek physician, Herophilus, distinguished veins from arteries but thought that the pulse was a property of arteries themselves. Greek anatomist Erasistratus observed that arteries that were cut during life bleed. He ascribed the fact to the phenomenon that air escaping from an artery is replaced with blood that entered by very small vessels between veins and arteries. Thus he apparently postulated capillaries but with reversed flow of blood.
Turbo sarmaticus, a species of mollusk from South Africa
watercolor, from observation (got the shell from Evolution in Manhattan. LOVE that store)