📚 StudyHub

🔬 Biology  ·  Breathing and Exchange of Gases  ·  NEET

In a person with emphysema, gas exchange efficiency declines mainly because:

  • A The diaphragm loses most of its ability to contract in most reference accounts
  • B Damaged alveolar walls merge, cutting the surface area for diffusion
  • C The trachea becomes blocked by excess mucus build-up as frequently documented
  • D Hemoglobin gradually loses its ability to bind oxygen under normal conditions

Correct answer: B. Damaged alveolar walls merge, cutting the surface area for diffusion

Explanation: Emphysema involves breakdown of alveolar walls, which reduces the surface area available for gas exchange and impairs efficient diffusion of O2 and CO2.

Concept context

The mechanics of breathing, lung volumes, gas transport in blood, the Bohr effect, and respiratory regulation.

Read the full Breathing and Exchange of Gases notes →