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Breathing and Exchange of Gases

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Biology

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Biology

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CBSE Gujarat Board Haryana Board

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Class 10 Class 12
Discuss the necessary features of a gas exchange surface.

Any surface that promotes the diffusion of gases must have following four basic features :

1. The surface area must have a relatively large surface area. Diffusion is a slow process, and the larger the area, the more is diffusion. Large surface area is maintained by extensive tissue projections and foldings.

2. The surface must be moist at all times, because oxygen and CO2 must be dissolved in water to diffuse across cell membranes. Aquatic organisms easily meet this requirement, but it is difficult for the organisms living on land to maintain a moist surface. Many adaptations in terrestrial organisms minimize but can never totally prevent water loss during respiration.

3. A surface for gas exchange must be close to the active cells of the body or to the fluid that transports gases between these cells and the surface. Diffusion is slow to carry gases very deeply into the body of an organism.

4. The membrane should be thin and permeable to the gases

124 Views

Oxygen is carried by haemoglobin as?

Oxyhaemoglobin.
415 Views

Name the cavity having lungs.

Thoracic cavity.
448 Views

70% of carbondioxide is transported as ?

Bicarbonate
360 Views

What is the partial pressure of oxygen in  oxygenated blood ?

95 mm Hg
702 Views

By what amount the solubility of carbondioxide is more than the solubility of oxygen?

20 - 25 times
414 Views