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THE TRANSPORT OF GAS BY THE BLOOD OF THE TURTLE
1Laboratories of Physiology in the Harvard Medical School, Boston.
The Journal of General Physiology
|October 30, 2009
Summary
Turtle blood, Pseudemys concinna, efficiently transports oxygen and carbon dioxide due to low cell volume and high bicarbonate levels. These factors influence gas exchange curves and distribution within the blood.
Area of Science:
- Comparative physiology
- Respiratory gas transport
Background:
- Understanding blood gas transport is crucial for respiratory physiology.
- Reptilian blood physiology offers insights into evolutionary adaptations.
Purpose of the Study:
- To characterize the blood of Pseudemys concinna for oxygen and carbon dioxide transport.
- To elucidate the relationship between blood composition and gas exchange properties.
Main Methods:
- Analysis of corpuscular content and bicarbonate concentration.
- Determination of carbon dioxide and oxygen dissociation curves.
- Investigation of hemoglobin's role in gas transport.
Main Results:
- Pseudemys concinna blood has low corpuscular content (10-22%) and high bicarbonate.
- These features fully explain carbon dioxide dissociation curve characteristics.
- Oxygen-combining capacity of turtle corpuscles equals human erythrocytes.
- Oxygen dissociation is similar to mammals, affected by carbon dioxide levels.
Conclusions:
- Turtle blood's unique composition optimizes gas transport.
- Hemoglobin's interaction with oxygen and carbon dioxide is key.
- Some blood characteristics remain unexplained by current chemical factors.
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