Physiology: An actively controlled heart valve

@article{Franklin2000PhysiologyAA,
  title={Physiology: An actively controlled heart valve},
  author={C. Franklin and M. Axelsson},
  journal={Nature},
  year={2000},
  volume={406},
  pages={847-848}
}
Vertebrate hearts typically have cardiac valves that are thin and leaf-like and which work passively, allowing blood to move forward during systole and preventing it from flowing back during diastole. Crocodilian hearts have nodules of connective tissue, resembling opposing knuckles, or cog-teeth, in the subpulmonary conus just proximal to the pulmonary valves. Here we show that these cog-teeth act in the estuarine crocodile Crocodylus porosus (Fig. 1) as a valve that regulates the flow of… Expand
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