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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
Cellular respiration takes place in
(a) Lysosome
(b) Chlorophyll
(c) Mitochondria
(d) Ribosome
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What organs are attached to the two bronchi?
State whether the following statement is true or false:
Fish and earthworm exchange gases during respiration in the same way.
Explain why, a land plant may die if its roots remain waterlogged for a long time.
What type of repiration takes place in yeast?
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 |
Which of the following increases in muscle cells when they are lacking in oxygen?
Which of the following is the correct sequence of air passage during inhalation?
(a) nostrils → larynx → pharynx → trachea → lungs
(b) nasal passage → trachea → pharynx → larynx → alveoli
(c) larynx → nostrils → pharynx → lungs
(d) nostrils → pharynx → larynx → trachea → alevoli
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During the deficiency of oxygen in tissues of human beings, pyruvic acid is converted into lactic acid in:
Some sugar solution is taken in a test-tube and a little of substance X in powder form is added to it. The mouth of test-tube is closed with a cork and allowed to stand for sometime. On opening the cork, a characteristic smell of substance Y is obtained and a gas Z is also observed to be formed. The gas Z extinguishes a burning matchstick.
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(b) What could organism Y be? Name the breathing organs B.
(c) What could organism Z be? Name the breathing organs C and D.
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Name the body structure concerned with the given functional activity:
Prevents food from entering the trachea during swallowing.
Given below is an overall chemical reaction of a certain process:
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Is this reaction applicable to animals or to plants or to both animals and plants?
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How much percent of C02 is transported in a dissolved form as carbonic acid?
Which is the correct sequence of air passage during inhalation?
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