NEET 1998 · Class 11

Breathing and Exchange of Gases

The exchange of gases in the alveoli of the lungs takes place by (1998)

  1. (A)passive transport
  2. (B)active transport
  3. (C)osmosis
  4. (D)simple diffusion

The NCERT line that answers it

Verbatim line

O<sub>2</sub> and CO<sub>2</sub> are exchanged in these sites by simple diffusion mainly based on pressure/concentration gradient.

Chapter
Breathing and Exchange of Gases
Section
14.3 EXCHANGE OF GASES
Page
6
Words matched
13 of 16

The answer appears as a continuous sentence in NCERT. This is that sentence.

How this line gives the answer

0, emb=1.0, combined=1.0). Verified: high — The span explicitly states that O2 and CO2 are exchanged 'by simple diffusion' in the alveoli, which directly matches the correct answer and distinguishes it from passive transport, active transport, and osmosis.

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