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4 - Oxygen uptake and transport in air breathers

Published online by Cambridge University Press:  05 June 2012

By
Nini Skovgaard ,
James W. Hicks  and
Tobias Wang
Edited by
Göran E. Nilsson
Göran E. Nilsson
Affiliation:
Universitetet i Oslo
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Summary

Introduction

Air-breathing vertebrates constitute a large group of diverse animals belonging to different taxonomic classes. Air breathing evolved independently in different groups of fish and early tetrapods, and extant species employ an array of different air-breathing organs that are derived from various existing structures, such as the gastrointestinal tract or the buccopharyngeal cavity (see Chapter 6). True lungs in terrestrial vertebrates develop embryologically as a ventral outpocketing of the posterior pharynx into a paired structure that extends into the peritoneal cavity. The entrance to the lung through the pharynx is guarded by the glottis, and the lungs are perfused by a pulmonary artery that carries oxygen-poor blood to the respiratory surfaces in the lungs, while a pulmonary vein returns oxygen-rich blood to the heart. Although the lungs of extant air-breathing vertebrates share a common embryological development and overall arrangement, there are large structural differences, from the simple sac-like lungs of amphibians to the complex structure of the alveolar lungs of mammals and the parabronchial lungs of birds. Regardless of the structural variation, in all air-breathing vertebrates the gas-exchange organs provide adequate exchange of O2 and CO2 to meet the variable metabolic needs of the animal.

Vertebrates supply the majority of their energetic requirements through aerobic metabolism. As the product of aerobic metabolism, adenosine triphospate (ATP), cannot be effectively stored, the oxygen-transport process represents a continual balance between delivery of oxygen (supply) and the use of ATP (demand).

Type
Chapter
Information
Respiratory Physiology of Vertebrates
Life With and Without Oxygen
 , pp. 95 - 128
Publisher: Cambridge University Press
Print publication year: 2010

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References

Aaronson, P. I., Robertson, T. P. and Ward, J. P. T. (2002). Endothelium-derived mediators and hypoxic pulmonary vasoconstriction. Respir. Physiol. Neurobiol., 132, 107–20.CrossRefGoogle ScholarPubMed
Andersen, J. B., Rourke, B. C., Caiozzo, V. J., Bennett, A. F. and Hicks, J. W. (2005). Postprandial cardiac hypertrophy in pythons. Nature, 434, 37–8.CrossRefGoogle ScholarPubMed
Axelsson, M., Fritsche, R., Holmgren, S., Grove, D. J. and Nilsson, S. (1991). Gut blood flow in the estuarine crocodile, Crocodylus porosus. Acta. Physiol. Scand., 142, 509–16.CrossRefGoogle ScholarPubMed
Bärtsch, P. (2007). Effect of altitude on the heart and lungs. Circulation, 116, 2191–202.CrossRefGoogle ScholarPubMed
Bennett, A. F. and Ruben, J. A. (1979). Endothermy and activity in vertebrates. Science, 206, 649–54.CrossRefGoogle ScholarPubMed
Bergman, N. M., Lenton, T. M. and Watson, A. J. (2004). COPSE: a new model of biogeochemical cycling over Phanerozoic time. Am. J. Sci., 304, 397–437.CrossRefGoogle Scholar
Berner, R. A. (1999). Atmospheric oxygen of the Phanerozoic time. Proc. Natl. Acad. Sci., 96, 10955–7.CrossRefGoogle ScholarPubMed
Berner, R. A. (2006) GEOCARBSULF: A combined model for Phanerozoic atmospheric O2 and CO2. Geochim. Cosmochim. Acta, 70, 5653–64.CrossRefGoogle Scholar
Berner, R. A., Vanden Brooks, J. M. and Ward, P. D. (2007). Oxygen and evolution. Science, 316, 557–8.CrossRefGoogle ScholarPubMed
Berner, R. A., Beerling, D. J., Dudley, R., Robinson, J. W. and Wildman, R. A., Jr. (2003). Phanerozoic atmospheric oxygen. Ann. Rev. Earth Planet Sci., 31, 105–34.CrossRefGoogle Scholar
Brainerd, E. L. and Owerkowicz, T. (2006). Functional morphology and evolution of aspiration breathing in tetrapods. Respir. Physiol. Neurobiol., 154, 73–88.CrossRefGoogle ScholarPubMed
Burggren, W. W. and Johansen, K. (1982). Ventricular hemodynamics in the monitor lizard Varanus exanthematicus: pulmonary and systemic pressure separation. J. Exp. Biol. 96, 343–54.Google Scholar
Burggren, W. W. and Moalli, R. (1984). ‘Active’ regulation of cutaneous gas exchange by capillary recruitment in amphibians: experimental evidence and a revised model for skin respiration. Respir. Physiol., 55, 379–92.CrossRefGoogle Scholar
Burggren, W. and Shelton, G. (1979). Gas exchange and transport during intermittent breathing in chelonian reptiles. J. Exp. Biol., 82, 75–92.Google Scholar
Burggren, W. W. and West, N. H. (1982). Changing respiratory importance of gills, lungs and skin during metamorphosisin the bullfrog Rana catesbeiana. Respir. Physiol., 47, 151–64.CrossRefGoogle ScholarPubMed
Burggren, W. W., Farrell, A. P. and Lillywhite, H. B. (1997). Vertebrate cardiovascular systems. In Handbook of Comparative Physiology, ed. Dantzler, W.. New York: Oxford University Press.Google Scholar
Carrier, D. R. and Farmer, C. G. (2000). The evolution of pelvic aspiration in archosaurs. Paleobiology, 26, 271–93.2.0.CO;2>CrossRefGoogle Scholar
Chan, T. and Burggren, W. W. (2005). Hypoxic incubation creates differential morphological effects during specific developmental critical windows in the embryo of the chicken (Gallus gallus). Respir. Physiol. Neurobiol., 145, 251–63.CrossRefGoogle Scholar
Claessens, L. P. A. M. (2004). Dinosaur gastralia: origin, morphology and function. J. Vertebr. Paleontol., 24, 89–106.CrossRefGoogle Scholar
Clark, T. D., Wang, T., Butler, P. J. and Frappell, P. B. (2005). Factorial scopes of cardiac-metabolic variables remain constant with changes in body temperature in the varanid lizard, Varanus rosenbergi. Am. J. Physiol., 288, R992–7.Google Scholar
Crossley, D. A., Wang, T. and Altimiras, J. (1998). Hypoxia elicits pulmonary vasoconstriction in anaesthetized turtles. J. Exp. Biol., 201, 3367–75.Google Scholar
Dempsey, J. A. and Wagner, P. D. (1999). Exercise-induced arterial hypoxemia. J. Appl. Physiol., 87, 1997–2006.CrossRefGoogle ScholarPubMed
Dempsey, J. A., Hanson, P. G. and Henderson, K. S. (1984). Exercise-induced arterial hypoxemia in healthy human subjects at sea level. J. Physiol., 355, 161–75.CrossRefGoogle ScholarPubMed
Dubach, M. (1981). Quantitative analysis of the respiratory system of the house sparrow, budgerigar, and violet-eared hummingbird. Respir. Physiol., 46, 43–60.CrossRefGoogle ScholarPubMed
Duncker, H-R. (1972). Structure of avian lungs. Respir. Physiol., 14, 44–63.CrossRefGoogle ScholarPubMed
Erwin, D. H. (1993). The Great Paleozoic Crisis: Life and Death in the Permian. New York: Columbia University Press.Google Scholar
Falkowski, P., Katz, K., Milligan, A., Fennel, K., Cramer, B., Aubry, M. P., et al. (2005). The rise of atmospheric oxygen levels over the past 205 million years and the evolution of large placental mammals. Science, 309, 2202–4.CrossRefGoogle Scholar
Faraci, F. M., Kilgore, D. L. and Fedde, M. R. (1984). Attenuated pulmonary pressor response to hypoxia in bar-headed geese. Am. J. Physiol., 247, R402–3.Google ScholarPubMed
Feder, M. E. and Burggren, W. W. (1985). Cutaneous gas exchange in vertebrates: design, patterns, control, and implications. Biol. Rev., 60, 1–45.CrossRefGoogle ScholarPubMed
Feder, M. E. and Pinder, A. W. (1988). Ventilation and its effect on ‘infinite pool’ exchangers. Am. Zool., 28, 973–83.CrossRefGoogle Scholar
Flück, M., Webster, K. A., Graham, J., Giomi, F., Gerlach, F. and Schmitz, A. (2007). Coping with cyclic oxygen availability: evolutionary aspects. Integr. Comp. Biol., 47, 524–31.CrossRefGoogle ScholarPubMed
Frappell, P., Schultz, T. and Christian, K. (2002). Oxygen transfer during aerobic exercise in a varanid lizard Varanus mertensi is limited by the circulation. J. Exp. Biol., 205, 2725–36.Google Scholar
Gamperl, A. K., Milsom, W. K., Farrell, A. P. and Wang, T. (1999). Cardiorespiratory responses of the toad (Bufo marinus) to hypoxia at two different temperatures. J. Exp. Biol., 202, 3647–58.Google ScholarPubMed
Glass, M. L. (1991). Pulmonary diffusion capacity of ectothermic vertebrates. In The Vertebrate Gas Transport Cascade, ed. Bicudo, J. E. P. W.. Boca Raton: CRC Press, pp. 154–61.Google Scholar
Gleeson, T. T., Mitchell, G. S. and Bennett, A. F. (1980). Cardiovascular responses to graded activity in the lizards Varanus and Iguana. Am. J. Physiol. 8, R174–9.Google Scholar
Graham, J. B., Dudley, R., Aguilar, N. and Gans, C. (1995). Implications of the late Paleozoic oxygen pulse for physiology and evolution. Nature, 375, 117–20.CrossRefGoogle Scholar
Harrison, J., Frazier, M. R., Henry, J. R., Kaiser, A., Klok, C. J. and Rascon, B. (2006). Responses of terrestrial insects to hypoxia or hyperoxia. Respir. Physiol. Neurobiol., 154, 4–17.CrossRefGoogle ScholarPubMed
Hedrick, M. S., Palioca, W. B. and Hillman, S. S. (1999). Effects of temperature and physical activity on blood flow shunts and intracardiac mixing in the toad Bufo marinus. Physiol. Biochem. Zool., 72, 509–19.CrossRefGoogle ScholarPubMed
Hicks, J. W. (1998). Cardiac shunting in reptiles: Mechanism, regulation, and physiological functions. In Biology of the Reptilia, Vol. 19 (Morphology), ed. Gans, C. and Gaunt, S.. Ithaca: Society for the Study of Amphibians and Reptiles, pp. 425–83.Google Scholar
Hicks, J. W. and Wang, T. (1996). Functional role of cardiac shunts in reptiles. J. Exp. Zool. 275, 204–16.3.0.CO;2-J>CrossRefGoogle Scholar
Hicks, J. W. and Wang, T. (2004). Hypometabolism in reptiles: behavioural and physiological mechanisms that reduce aerobic demands. Resp. Physiol. Neurobiol., 141, 261–71.CrossRefGoogle ScholarPubMed
Hicks, J. W. and White, F. N. (1992). Ventilation and gas exchange during intermittent ventilation in the American alligator, Alligator mississippiensis. Respir. Physiol., 88, 23–36.CrossRefGoogle Scholar
Hicks, J. W., Wang, T. and Bennett, A. F. (2000). Patterns of cardiovascular and ventilatory response to elevated metabolic states in the lizard, Varanus exanthematicus. J. Exp. Biol., 203, 2437–45.Google Scholar
Hicks, J. W., Ishimatsu, A., Molloi, S., Erskin, A. and Hesiler, N. (1996). The mechanism of cardiac shunting in reptiles: a new synthesis. J. Exp. Biol., 199, 1435–46.Google ScholarPubMed
Hopkins, S. R. (2006). Exercise induced arterial hypoxemia: the role of ventilation-perfusion inequality and pulmonary diffusion limitation. In Hypoxia and Exercise; Advances in Experimental Medicine and Biology. Berlin: Springer-Verlag, pp. 17–30.CrossRefGoogle Scholar
Hopkins, S. R., Wang, T. and Hicks, J. W. (1996). The effect of altering pulmonary blood flow on pulmonary gas exchange in the turtle Trachemys (Pseudemys) scripta. J. Exp. Biol., 199, 2207–14.Google ScholarPubMed
Hopkins, S. R., Hicks, J. W., Cooper, T. K. and Powell, F. L. (1995). Ventilation and pulmonary gas exchange during exercise in the Savanna monitor lizard (Varanus exanthematicus). J. Exp. Biol., 198, 1783–9.Google Scholar
Hopkins, S. R., Stary, C. M., Falor, E., Wagner, H., Wagner, P. D. and McKirnan, M. D. (1999). Pulmonary gas exchange during exercise in pigs. J. Appl. Physiol,. 86, 93–100.CrossRefGoogle ScholarPubMed
Hochachka, P. W., Lutz, P. L. (2001). Mechanism, origin, and evolution of anoxia tolerance in animals. Comp. Biochem. Physiol. 130B, 435–59.CrossRefGoogle Scholar
Hochachka, P. W., Buck, L. T., Doll, C. J. and Land, S. C. (1996). Unifying theory of hypoxia tolerance: molecular/metabolic defense and rescue mechanisms for surviving oxygen lack. Proc. Natl. Acad. Sci. USA, 93, 9493–8.CrossRefGoogle ScholarPubMed
Huey, R. B. and Ward, P. D. (2005). Hypoxia, global warming, and terrestrial Late Permian extinctions. Science, 308, 398–401.CrossRefGoogle ScholarPubMed
Ishimatsu, A., Hicks, J. W. and Heisler, N. (1996). Analysis of cardiac shunting in the turtle Trachemys (Pseudemys) scripta: application of the three outflow vessel model. J. Exp. Biol., 199, 2667–77.Google ScholarPubMed
Kaiser, A., Klok, J. C., Socha, J. J., Lee, W.-K., Quinlan, M. C. and Harrison, J. F. (2007). Increase in tracheal investment with beetle size supports hypothesis of oxygen limit on insect gigantism. Proc. Natl. Acad. Sci., 104, 13198–203.CrossRefGoogle ScholarPubMed
Klein, W. and Owerkowicz, T. (2006). Function of intracoelomic septa in lung ventilation of amniotes: lessons from lizards. Physiol. Biochem. Zool., 79, 1019–32.CrossRefGoogle ScholarPubMed
Krogh, A. (1919). The supply of oxygen to the tissues and the regulation of the capillary circulation. J. Physiol., 52, 457–74.CrossRefGoogle ScholarPubMed
Krogh, A. and Krogh, M. (1910). On the rate of diffusion of CO into the lungs of man. Skand. Arch. Physiol., 23, 236–47.CrossRefGoogle Scholar
Krosniunas, E. H. and Hicks, J. W. (2003). Cardiac output and shunt during voluntary activity at different temperatures in the turtle, Trachemys scripta. Physiol. Biochem. Zool., 76, 679–94.CrossRefGoogle ScholarPubMed
Maina, J. N. (1998). The Gas Exchangers: Structure, Function and Evolution of the Respiratory Processes. Heidelberg: Springer-Verlag.CrossRefGoogle Scholar
Maina, J. N. (2006). Development, structure, and function of a novel respiratory organ, the lung-air sac system of birds: to go where no other vertebrate has gone. Biol. Rev., 81, 545–79.CrossRefGoogle ScholarPubMed
Maina, J. N. and West, J. B. (2005). Thin and strong! The bioengineering dilemma in the structural and functional design of the blood-gas barrier. Physiol. Rev., 85, 811–44.CrossRefGoogle ScholarPubMed
Maina, J. N., King, A. S. and King, D. Z. (1982). A morphometric analysis of the lungs of a species of bat. Respir. Physiol., 50, 1–11.CrossRefGoogle ScholarPubMed
Malvin, G. M. (1988). Microvascular regulation of cutaneous gas exchange in amphibians. Am. Zool., 28, 999–1007.CrossRefGoogle Scholar
Malvin, G. M. and Walker, B. R. (2001). Sites and ionic mechanisms of hypoxic vasoconstriction in frog skin. Am. J. Physiol., 280, R1308–14.Google ScholarPubMed
Milsom, W. K. (1991). Intermittent breathing in reptiles. Annu. Rev. Physiol., 53, 87–105.CrossRefGoogle Scholar
Mitchell, G. S., Gleeson, T. T. and Bennett, A. F. (1981). Pulmonary oxygen transport during activity in lizards. Respir. Physiol. 43, 365–75.CrossRefGoogle ScholarPubMed
Mortensen, S. P., Damsgaard, R., Dawson, E. A., Secher, N. H. and González-Alonso, J (2008). Restrictions in systemic and locomotor skeletal muscle perfusion, oxygen supply and VO2 during high-intensity whole-body exercise in humans. J. Physiol., 586, 2621–35.CrossRefGoogle ScholarPubMed
Moudgil, R., Michelakis, E. D. and Archer, S. L. (2005). Hypoxic pulmonary vasoconstriction. J. Appl. Physiol., 98, 390–403.CrossRefGoogle ScholarPubMed
O'Connor, P. M. and Claessens, L. P. A. M. (2004). Basic avian pulmonary design and flow-through ventilation in non-avian theropod dinosaurs. Nature, 436, 253–6.CrossRefGoogle Scholar
Owerkowicz, T., Elsey, R. E. and Hicks, J. W. (2009). Atmospheric oxygen affects growth trajectory, cardiopulmonary allometry and metabolic rate in the American alligator (Alligator mississipiensis). J. Exp. Biol. 212, 1237–47.CrossRefGoogle Scholar
Owerkowicz, T., Farmer, C. G., Hicks, J. W. and Brainerd, E. L. (1999). Contribution of gular pumping to lung ventilation in monitor lizards. Science, 284, 1661–3.CrossRefGoogle ScholarPubMed
Perry, S. F. (1989). Mainstreams in the evolution of vertebrate respiratory structures. In Form and Function in Birds, Vol. 4, ed. King, A. S. and McMelland, J.. London: Academic Press, pp. 1–67.Google Scholar
Piiper, J. (1961). Unequal distribution of pulmonary diffusing capacity and the alveolar-arterial PO2 differences: theory. J. Appl. Physiol., 16, 493–8.CrossRefGoogle Scholar
Piiper, J. (1990). Modelling of gas exchange in lung gills and skin. In Vertebrate Gas Exchange: from Environment to Cell, ed. Boutillier, R. G.. Berlin: Springer-Verlag, pp. 5–44.Google Scholar
Piiper, J. (1993). Medium-blood gas exchange: diffusion, distribution and shunt. In The Vertebrate Gas Transport Cascade, ed. Bicudo, J. E. P. W.. Boca Raton: CRC Press, pp. 106–120.Google Scholar
Piiper, J. and Scheid, P. (1972). Maximum gas transfer efficacy of models for fish gills, avian lungs and mammalian lungs. Respir. Physiol., 14, 115–24.CrossRefGoogle ScholarPubMed
Piiper, J. and Scheid, P. (1975). Gas transport efficacy of gills, lungs and skin: theory and experimental data. Respir. Physiol., 23, 209–21.CrossRefGoogle ScholarPubMed
Piiper, J. and Scheid, P. (1977). Comparative physiology of respiration: Functional analysis of gas exchange organs in vertebrates. In International Review of Physiology: Respiratory Physiology II, Vol. 14, ed. Widdecombe, J. G.. Boston: University Park Press, pp. 220–53.Google Scholar
Powell, F. L. and Gray, A. T. (1989). Ventilation-perfusion relationships in alligators. Respir. Physiol., 78, 83–94.CrossRefGoogle ScholarPubMed
Powell, F. L. and Hopkins, S. R. (2004). Comparative physiology of lung complexity: implications for gas exchange. News Physiol. Sci., 19, 55–60.Google ScholarPubMed
Ruben, J. A., Jones, T. D., Geist, N. R. and Híllenius, W. J. (1997). Lung structure and ventilation in therapod dinosaurs and early birds. Science 278, 1267–70.CrossRefGoogle Scholar
Scheid, P. and Piiper, J. (1997). Vertebrate respiratory physiology. In Comparative Physiology, Section 13, Vol. 1, ed. Dantzler, W. H.. New York: American Physiological Society, pp. 309–56.Google Scholar
Schmitt, P. M., Powell, F. L. and Hopkins, S. R. (2002). Ventilation-perfusion inequality during normoxic and hypoxic exercise in the emu. J. Appl. Physiol., 93, 1980–6.CrossRefGoogle ScholarPubMed
Seaman, J., Erickson, B. K., Kubo, K., et al. (1995). Exercise induced ventilation/perfusion inequality in the horse. Equine Vet. J., 27, 104–9.CrossRefGoogle Scholar
Secor, S. M., Hicks, J. W. and Bennett, A. F. (2000). Ventilatory and cardiovascular responses of pythons (Python molurus) to exercise and digestion. J. Exp. Biol., 203, 2447–54.Google ScholarPubMed
Skovgaard, N. and Wang, T. (2006). Local control of pulmonary blood flow and lung structure in reptiles: implications for ventilation perfusion matching. Respir. Physiol. Neurobiol, 154, 107–17.CrossRefGoogle ScholarPubMed
Skovgaard, N., Abe, A. S.Andrade, D. V. and Wang, T. (2005). Hypoxic pulmonary vasoconstriction in reptiles: a comparative study on four species with different lung structures and pulmonary blood pressures. Am. J. Physiol., 289, R1280–8.Google ScholarPubMed
Smith, M. P., Russell, M. J., Wincko, J. T. and Olson, K. R. (2001). Effects of hypoxia on isolated vessels and perfused gills of rainbow trout. Comp. Biochem. Physiol., 130A, 171–81.CrossRefGoogle Scholar
Starck, J. M. and Wimmer, C. (2005). Patterns of blood flow during the postprandial response in ball pythons, Python regius. J. Exp. Biol., 208, 881–9.CrossRefGoogle ScholarPubMed
Taylor, C. R. and Weibel, E. R. (1981). Design of the mammalian respiratory system. I. Problem and strategy. Respir. Physiol. 44, 1–10.CrossRefGoogle ScholarPubMed
Taylor, E. W, Andrade, D., Abe, A. S., Leite, Cleo A. C. and Wang, T. (2009). The unequal influences of the left and right vagi on the control of the heart and pulmonary artery in the rattlesnake, Crotalus durissus. J. Exp. Biol. 212, 145–51.CrossRefGoogle ScholarPubMed
Vanden Brooks, J. M., (2004). The effects of varying pO2 levels on vertebrate evolution. J. Vertebr. Paleontol., 24, 124A.Google Scholar
Euler, U. S. and Liljestrand, G. (1946). Observations on the pulmonary arterial blood pressure in the cat. Acta Physiol. Scand., 12, 301–20.CrossRefGoogle Scholar
Wagner, P. D. (1996). Determinants of maximal oxygen transport and utilization. Ann. Rev. Physiol., 58, 21–50.CrossRefGoogle ScholarPubMed
Wagner, P. D., Naumann, P. F. and Laravuso, R. B. (1974a). Simultaneous measurements of eight foreign gases in blood by gas chromatography. J. Appl. Physiol., 36, 600–5.CrossRefGoogle Scholar
Wagner, P. D., Saltzman, H. A. and West, J. B. (1974b). Measurement of continuous distribution of ventilation-perfusion ratios: theory. J. Appl. Physiol., 36, 588–99.CrossRefGoogle Scholar
Wang, T. and Hicks, J. W. (1996). Cardiorespiratory synchrony in turtles. J. Exp. Biol., 199, 1791–800.Google ScholarPubMed
Wang, T. and Hicks, J. W. (2002). An integrative model to predict maximum oxygen uptake of animals with central vascular shunts. Zoology, 105, 45–53.CrossRefGoogle ScholarPubMed
Wang, T. and Hicks, J. W. (2004). Why Savannah monitor lizards hyperventilate during activity: a comparison of model predictions and experimental data. Respir. Physiol. Neurobiol., 141, 261–71.Google Scholar
Wang, T. and Hicks, J. W. (2008). Changes in pulmonary blood flow do not affect gas exchange during intermittent ventilation in resting turtles. J. Exp. Biol., 211, 3759–63.CrossRefGoogle Scholar
Wang, T., Abe, A. S. and Glass, M. L. (1998a). Effects of temperature on lung and blood gases in the South American rattlesnake, Crotalus durissus terrificus. Comp. Biochem. Physiol., 121A, 7–11.CrossRefGoogle Scholar
Wang, T., Busk, M. and Overgaard, J. (2001a). The respiratory consequences of feeding in amphibians and reptiles. Comp. Biochem. Physiol. 128A, 533–47.CrossRefGoogle Scholar
Wang, T., Carrier, D. R. and Hicks, J. W. (1997). Ventilation and gas exchange in lizards during treadmill exercise. J. Exp. Biol. 200, 2629–39.Google ScholarPubMed
Wang, T., Smits, A. W. and Burggren, W. W. (1998b). Pulmonary functions in reptiles. In Biology of the Reptilia, Vol. 19 (Morphology), ed. Gans, C. and Gaunt, S.. Ithaca: Society for the Study of Amphibians and Reptiles, pp. 297–374.Google Scholar
Wang, T., Altimiras, J., Klein, W. and Axelsson, M. (2003). Ventricular haemodynamics in Python molurus: separation of pulmonary and systemic pressures. J. Exp. Biol. 206, 4241–5.CrossRefGoogle ScholarPubMed
Wang, T., Warburton, S. J., Abe, A. S. and Taylor, E. W. (2001b). Vagal control of heart rate and cardiac shunts in reptiles: relation to metabolic state. Exp. Physiol. 86, 777–86.CrossRefGoogle ScholarPubMed
Ward, P. D., Labandeira, C., Laurin, M., Berner, R. A. (2006). Confirmation of Romer's Gap as a low oxygen interval constraining the timing of initial arthropod and vertebrate terrestrialization. Proc Natl Acad Sci, 103, 16818–22.CrossRefGoogle ScholarPubMed
Weibel, E. R. and Gomez, D. M. (1962). Architecture of the human lung. Science, 137, 577–85.CrossRefGoogle ScholarPubMed
Weir, E. K. and Archer, S. L. (1995). The mechanism of acute hypoxic pulmonary vasoconstriction: the tale of two channels. FASEB J, 9, 183–9.CrossRefGoogle ScholarPubMed
West, J. B. (2003). Thoughts on the pulmonary blood-gas barrier. Am. J. Physiol., 285, L501–13.Google ScholarPubMed
Wood, S. C. (1982). Effect of O2 affinity on arterial PO2 in animals with central vascular shunts. J. Appl. Physiol. 53, 1360–4.CrossRefGoogle ScholarPubMed
Wood, S. C. (1984). Cardiovascular shunts and oxygen transport in lower vertebrates. Am. J. Physiol. 247, R3–14.Google ScholarPubMed
Wood, S. C. (1991). Interactions between hypoxia and hypothermia. Annu. Rev. Physiol. 53, 71–85.CrossRefGoogle ScholarPubMed

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