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Breathing and respiration

Breathing is the act of inhaling and exhaling air.

Respiration is interchange of gases between an organism and the medium in which it lives.

Comparison between Breathing and respiration: compared

Comparison between Breathing and respiration: compared





Is simple intake of fresh air and removal of foul air

Is oxidation of food to form CO2, water and energy


It is a physical process

It is a biochemical process


No energy is released

Energy is released in the form of ATP


It occurs outside the cell so it is an extracellular process

Occurs… (21 more words) …

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Surface tension and surfactant

Surface tension is the force caused due to intermolecular attraction between the molecules on the surface because of which alveoli tend to collapse. In order to prevent this collapse the alveoli are lined by surface tension reducing substance called surfactant.

Surfactants are substances which reduce surface tension. Chemically it is Dipalmitoyal phosphatidylcholine. Production of surfactant starts by seventh month of intrauterine life.


  • It reduces surface tension, thus prevents collapse of alveoli

  • It reduces respiratory effort by keeping the alveoli open.

Understanding the surface tension and surfactant

Understanding the Surface Tension and Surfactant

What is difference between surface tension and surfactant

Infant Respiratory Distress Syndrome is… (41 more words) …

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