State two differences between the air found in the alveoli and the air which is breathed in.

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jgeertz eNotes educator| Certified Educator

Oxygen enters lungs with each inhalation and carbon dioxide exits the lungs with each exhalation. This process is called pulmonary ventilation.

The exchange of these gases occurs between the alveoli, tiny air-filled sacs in the lungs, and the blood. This process is called external respiration.

Two differences between pulmonary ventilation and external respiration:

pulmonary respiration -

1. movement of air occurs due to pressure gradients

2. it is a mechanical process of moving air in and out of the lungs

external respiration -

1. movement of respiratory gases involves diffusion across a respiratory membrane

2. alveoli/capillary gas exchange is a biochemical process

lnj100 | Student
    1. The act or process of inhaling and exhaling; breathing. Also called ventilation.
    2. The act or process by which an organism without lungs, such as a fish or plant, exchanges gases with its environment.
    1. The oxidative process occurring within living cells by which the chemical energy of organic molecules is released in a series of metabolic steps involving the consumption of oxygen and the liberation of carbon dioxide and water.
    2. Any of various analogous metabolic processes by which certain organisms, such as fungi and anaerobic bacteria, obtain energy from organic molecules.
respirational res'pi·ra'tion·al adj.

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