Tag: respiratory cycle
Questions Related to respiratory cycle
Percentage of O$ _2$ present in inhaled air in man is about
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21%
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78%
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1%
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43%
Inhaled air contains more oxygen used to create energy and less carbon dioxide. Exhaled air which contains more carbon dioxide produced as a waste product of energy production and less oxygen as it has been used in respiration. Inhaled air contains 21% oxygen, 0.04% CO$ _2$ and 79% N$ _2$. Exhaled air contains 16% oxygen, 4% CO$ _2$ and 79% N$ _2$.
During inspiration, the diaphragm
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Becomes dome-shaped
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Flattens
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Remains unchanged
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Rotates sidewise
The diaphragm is located below the lungs and is the major muscle of respiration. It is large, dome-shaped muscle that contracts rhythmically and continually. upon inhalation, the diaphragm contracts and flattens and the chest cavity enlarges. This contraction creates a vacuum, which pulls air into the lungs. Upon exhalation, the diaphragm relaxes and returns to its dome-like shape, and is forced out of the lungs.
Therefore, the correct answer is option B.
In man, expired air contains oxygen about
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4%
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10%
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16%
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20%
Inhaled air contains more oxygen used to create energy and less carbon dioxide. Exhaled air which contains more carbon dioxide produced as a waste product of energy production and less oxygen as it has been used in respiration. Inhaled air contains 21% oxygen, 0.04% CO$ _2$ and 79% N$ _2$. Exhaled air contains 16% oxygen, 4% CO$ _2$ and 79% N$ _2$.
The volume of thoracic cavity increases during
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Never
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Expiration
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Both A and B
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Inspiration
Increase in volume of thoracic cavity is seen in case of inspiration. Inspiration results in flattened diaphragm. The volume of thoracic cavity decreases during expiration and the diaphragm relaxes and comes to its original dome shape.
Fill in the blanks:
Component Inspired air Expired air
Oxygen a 16.4%
Nitrogen 79% b
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a = 5.6%, b = 21.6%
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a = 20.96%, b = 79.6%
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a = 28.8, b = 98%
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a = 1%, b = 2%
Component Inspired air Expired air
During forced expiration, actively contracting muscles include the
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Diaphragm
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External intercostals
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Abdominal muscles
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Diaphragm and intestinal muscle
The most important muscles of forced expiration are those of the abdominals. When these muscles contract, intra-abdominal pressure is raised, and the diaphragm is pushed upward. These muscles also contract forcefully during coughing, vomiting, and defecation. The internal intercostal muscles assist active expiration by pulling the ribs downward and inward thus decreasing the thoracic volume.
The exchange of gases in the alveoli of the lungs takes place by
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Osmosis
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Simple diffusion
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Passive transport
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Active transport
Which of the following activity does not take place during pulmonary respiration?
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Movement of buccal cavity
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Contraction and relaxation of sternohyal and pterohyal muscles
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Successive opening and closing of mouth and external nostrils
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All of the above
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No activity takes place
- Breathing or pulmonary ventilation leading to exchange of oxygen and carbon dioxide between the atmospheric air and the lungs
- Exchange of gases at the alveolar surface
- Transport and exchange of gases in the tissues
- Cellular respiration
The O$ _2$ in the exhaled air is
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About 8%
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About 10%
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About 15%
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About 20%
In respiration, the human body exhales about 15% of the oxygen that is not utilized by the body.
In human beings, rib case and sternum move upwardly and outwardly during.
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Exercise
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Sudden back injury
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Expiration
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Inspiration