Term
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Definition
| Exchange of gases between an organism and its external environment, the transport of these gases within the organism, and the idffusion of gases into and out of cells. |
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Term
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Definition
1. External nares (nostrils)
2. Nasal cavities: filtered by mucous and nasal hairs.
3. Pharynx
4. Larynx
5. Trachea: divides into 2 bronchi; Lined with ciliated epithelial cells which trap foregin particles.
6. Bronchioles: Terminal branches of bronchi. Each surrounded by alveoli. |
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Term
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Definition
| Small air sacs surrounding each bronchiole. Site of gas exchange between lungs and circulatory system. Each coated with a thin layer of liquid w/surfactant; surrounded by capillary network. |
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Term
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Definition
| Lowers the surface tension of the alveoli and facilitates gas exchange across the membranes. |
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Term
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Definition
| Process by which air is inhaled and exhaled. Purpose is to take in oxygen, and eliminate CO2. |
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Term
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Definition
| Body cavity that contains the heart and lung. Ventilating mechanism is dependent upon pressure changes in this cavity. |
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Term
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Definition
| Muscle which separates thoracic cavity from the abdominal cavity; bounded on the sides by the chest wall. |
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Term
| Visceral and parietal pleura |
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Definition
| Membranes surrounding the lungs. |
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Term
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Definition
| Region between the two pleura, which contains a thin layer of fluid. Pressure differential between this space and the lungs prevents the lungs from collapsing. |
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Term
| Inhalation: Negative-Pressure breathing. |
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Definition
1. Diaphragm contracts and flattens.
2. external intercostal muscles contract
3. Rib cage is and chest wall are pushed up and out.
4. Thoracic cavity increases in volume, which reduces the intrapleural pressure, causing lungs to expand and fill with air. |
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Term
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Definition
Passive Process
1. Diaphragm and external intercostal muscles relax, chest wall pushes inward.
2. = Decrease in thoracic cavity volume.
3. Causes air pressure in intrapleural space to increase.
4. Lungs deflate, air is forced out of the alveoli.
Forced:
1. Internal intercostal muscles contract.
2. Rib cage pulled down. |
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Term
| Regulation of ventilation |
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Definition
| Regulated by respiratory center in the medulla oblongata. |
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Term
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Definition
| Neurons in this area regulate ventilation via rhythmic discharges stimulating contraction of the intercostal muscles and/or diaphragm. Modified by chemoreceptors. |
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Term
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Definition
| Receptors which respond to changes in the pH and pp of CO2 in the blood, thereby stimulating an increase or decrease in ventilation rate. |
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Term
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Definition
| Measures amount of air normally in the respiratory system and the rate at which ventilation occurs. |
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Term
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Definition
| The maximum amount of air that can be forcibly inhaled and exhaled from the lungs. |
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Term
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Definition
| The amount of air normally inhaled and exhaled with each breath. |
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Term
| Expiratory reserve volume |
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Definition
| Volume of air that can still be forcibly exhaled following a normal exhalation. |
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Term
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Definition
| = vital capacity + residual volume. |
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Term
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Definition
| Dense network of minute blood vessels which surround the alveoli via which gas exchang eoccurs by diffusion (as well as alveoli). |
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