Because ambient air is a gas, it obeys the gas laws.

The composition of a gas mixture can be described in terms of either gas fractions or the corresponding partial pressure. Ambient air is a gas mixture composed of N 2 and O 2, with minute quantities of CO 2, argon, and inert gases. Alveolar ventilation thus begins with ambient air.

Inspiration brings ambient air to the alveoli, where O 2 is taken up and CO 2 is excreted. In an average-sized adult at rest, tidal volume is 500 mL. Tidal volume varies with age, gender, body position, and metabolic activity. Where f is the frequency or number of breaths per minute and TV, also known as V T, is the tidal volume, or volume of air inspired (or exhaled) per breath. As previously described, minute (or total) ventilation (V E) is the volume of air that enters or leaves the lung per minute and it is described by Ventilation is the process by which air moves in and out of the lung. This relationship is called the V/Q ratio.

However, the major determinant of normal gas exchange and thus the level of P o 2 and P co 2 in blood is the relationship between ventilation and perfusion. Ventilation and pulmonary blood flow (perfusion) are important components of gas exchange in the lung. 2.9) 22 Ventilation (V), Perfusion (Q), and V/Q Relationships Printed from STUDENT CONSULT: Berne and Levy Physiology 6E - The Online Medical Library for Students plus USMLE Steps 123 (ver.

Fowler anatomical dead space