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प्रश्न
How are the lungs designed in human beings to maximize the area for exchange of gases?
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उत्तर १
Lungs contain millions of alveoli which provide a surface for the exchange of gases. An extensive network of blood vessels is present in the wall of the alveoli. By lifting our ribs and flatten the diaphragm, the chest cavity becomes spacious. Air is sucked into the lungs and alveoli. The oxygen from the breath, diffuses into the blood and CO2 from the blood brought from the body, diffuses out into the air.
उत्तर २
- Human lungs contain a highly branched system of respiratory tubes. A primary bronchus splits into secondary bronchi, which then form tertiary bronchi. Each tertiary bronchus further divides into bronchioles that end in alveoli. Alveoli are small, rounded, thin-walled pouches with a network of capillaries.
- Gas exchange occurs in the alveoli, which is why each alveolus is considered a miniature lung. The alveoli offer a large surface area for gas exchange. Oxygen diffuses from the alveoli into the pulmonary capillaries, while carbon dioxide diffuses from the capillaries into the alveoli. The total surface area of the alveoli in human lungs is estimated to be about 100 m².
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संबंधित प्रश्न
How are oxygen and carbon dioxide transported in human beings?
Out of photosynthesis and respiration in plants, which process occurs:
(a) all the time?
(b) only at daytime?
Which of the following is correct for the process of anaerobic respiration?
| Carbon dioxide always produced | A lot of energy released | |
| (a) | No | Yes |
| (b) | No | No |
| (c) | Yes | No |
| (d) | Yes | Yes |
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During the deficiency of oxygen in tissues of human beings, pyruvic acid is converted into lactic acid in:
Which of the following statements are true about respiration?
(i) during inhalation, ribs move inward and diaphragm is raised.
(ii) the gaseous exchange takes place in the alveoli.
(iii) haemoglobin has greater affinity for carbon dioxide than oxygen.
(iv) alveoli increase surface area of the exchange of gases
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(b) Name (i) P (ii) Q (iii) R, and (iv) S.
(c) Which organism/organisms undergo aerobic respiration?
(d) Which organism/organisms undergo anaerobic respiration?
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(b) Which of the animals could be frog?
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(c) What type of respiration is exhibited by X in the above process?
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Trachea, Bronchus, Alveolus, Diaphragm
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Oxyhaemoglobin, Carbaminohaemoglobin, Hypoxia, Carboxyhaemoglobin
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Transports oxygen to the body cells.
Name the body structure concerned with the given functional activity:
Combines with the oxygen in the lungs.
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