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19 Cards in this Set
- Front
- Back
What are the stages involved in physiological respiration? |
Ventilation Cell respiration |
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Define ventilation |
The physical act of breathing to exchange oxygen between the atmosphere and the lungs |
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Define gas exchange |
The exchange of oxygen and CO2 between the alveoli and blood stream via passive diffusion |
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Arrange in the order in which oxygen travels into the lung: Bronchiole, Alveoli, Bronchus, Trachea, |
Trachea |
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Describe alveoli structure |
* One cell thick to minimize diffusion distance of gas, made of pneumocyte cells. * surrounded by capilaries * spherical in shape to maximise surface area * internal surface covered with liquid * pulmonary surfactant is used to reduce surface tension/keep the alveoli from adhering to itself. |
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Describe type I pneumocytes |
* involved in process of gas exchange * flat and thin to minimize diffusion distance * cells connected in tight junctions |
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Describe type II pneumocytes
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* responsible for secreting pulmonary surfactant (lubricant) to reduce surface tension * cubical in shape with many granules storing surfactant |
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What is the thoracic cavity? |
The chest |
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What happens when the volume of the thoracic cavity increase? |
Pressure in the thorax decrease |
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What happens when the volume of the thoracic cavity decrease? |
Pressure in the thorax increase |
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What happens during inspiration? |
Pressure in the thorax is less than atmospheric pressure, air moves into the lungs |
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What happens during expiration? |
Pressure in the thorax is greater than atmospheric pressure, air moves out of the lung |
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Why is it harder to breathe in high altitudes? |
Atmospheric pressure is lower, so a greater increase in chest volume is required for inspiration |
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How can athletes train for competitions? |
Under high altitude, the body can adapt to these conditions, making high altitude training effective for athletes |
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What happens when inspiratory muscles contract and why? |
Expiratory muscles relax, because they are antagonistic muscles |
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What muscles contract during inspiration? |
Diaphragm muscles external intercostals |
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What muscles contract and relax during expiration? |
Diaphragm relaxes internal intercostal muscles |
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What causes an increase in levels of ventilation (like after physical activity) |
* increased demand for ATP increases rate of cellular respiration, producing more CO2 * changes in blood CO2 levels are detected by sensors in artery walls, sending a signal to the brain * demand for gas exchange increase |
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How can ventilation in humans be measured? |
* chest belt and pressure meter * spirometer - recording the volume/speed of gas expelled at each breath |