Another diagram found almost ubiquitously in textbooks of anatomy and physiology is a schematic representation of the circulation(s) of the blood. I say 'almost ubiquitously' because I have never found a textbook in which some such diagram has never appeared... but there may be one out there somewhere. I also use the word 'circulation(s)' because human blood circulates in a figure of eight. One circuit is referred to as the systemic circulation, the other the pulmonary circulation.
Despite the conceptual simplicity of the circulation of the blood, the diagrams one finds in textbooks vary markedly. I shall share some of those I have collected from time to time. To begin, this version comes from Wikipedia:
As with all diagrams, there is simplification, conceptualisation and questions arising as a result. The more commonly a diagram is found in a textbook, the more it should be scrutinised. New textbooks take their lead from old textbooks. Some things are included because they have always been included; their exclusion might be deemed an omission. (Nobody wants a bad review.)
Is this the best such diagram? Does it make its point as well as it could?
