1. In both Pseudemys and Testudo, blood pressures are identical in all chambers of the ventricle. Systolic pressures are not measurably different in the ventricle and systemic arteries but are 0–5-2-0 cm H2O lower in the pulmonary artery due to the resistance of the pulmonary outflow tract. Diastolic pressures are the same in all systemic arteries but are substantially lower in the pulmonary artery. It is concluded that the systemic and pulmonary circulations are perfused by a single pump during both apnoea and lung ventilation. 2. Flow profiles in pulmonary and systemic arteries are characteristicallly different. Substantial changes in cardiac output may occur during intermittent breathing and apnoea, especially if there are large fluctuations in heart rate. Pulmonary flow increases during lung ventilation due to vasodilation of the lung vasculature. Systemic is also affected though the increase is usually smaller. 3. Any separation in the blood pumped by the single ventricle must be maintained by laminar flow patterns and the composition of the blood in each of the major arteries should reflect their relationship to these patterns.
Cardiovascular dynamics of the chelonia during apnoea and lung ventilation
G. Shelton, W. Burggren; Cardiovascular dynamics of the chelonia during apnoea and lung ventilation. J Exp Biol 1 April 1976; 64 (2): 323–343. doi: https://doi.org/10.1242/jeb.64.2.323
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Celebrating 100 years of discovery
We are proud to be celebrating 100 years of discovery in Journal of Experimental Biology. Visit our centenary webpage to find out more about how we are marking this historic milestone.
Craig Franklin launches our centenary celebrations
Editor-in-Chief Craig Franklin reflects on 100 years of JEB and looks forward to our centenary celebrations, including a supplementary special issue, a new early-career researcher interview series and the launch of our latest funding initiatives.
Looking back on the first issue of JEB
Journal of Experimental Biology launched in 1923 as The British Journal of Experimental Biology. As we celebrate our centenary, we look back at that first issue and the zoologists publishing their work in the new journal.
Biology Communication Workshop: Engaging the world in the excitement of research
We are delighted to be sponsoring a Biology Communication Workshop for early-career researchers as part of JEB’s centenary celebrations. The workshop focuses on how to effectively communicate your science to other researchers and the public and takes place the day before the CSZ annual meeting, on 14 May 2023. Find out more and apply here.
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