Skip to main content
Ch. 22 The Respiratory System
Marieb - Human Anatomy & Physiology 11th Edition
Marieb, Hoehn11th EditionHuman Anatomy & PhysiologyISBN: 9780136874034Non è quello che usi tu?Cambia libro di testo
Capitolo 22, Problema 5

Which of the following determines the direction of gas movement?
a. Solubility in water
b. Partial pressure gradient
c. Temperature
d. Molecular weight and size of the gas molecule

Guida verificata passo dopo passo
1
Understand that gas movement, especially in biological systems like the lungs, occurs primarily by diffusion.
Recall that diffusion of gases depends on differences in partial pressures, which create a gradient that drives gas molecules from areas of higher partial pressure to areas of lower partial pressure.
Recognize that while solubility, temperature, and molecular weight can affect the rate of diffusion, they do not determine the direction of gas movement.
Identify that the key factor determining the direction of gas movement is the partial pressure gradient, because gases move down their partial pressure gradients.
Conclude that among the options given, the partial pressure gradient (option b) is the correct determinant of the direction of gas movement.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
1m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Partial Pressure Gradient

The partial pressure gradient refers to the difference in the partial pressures of a gas between two areas. Gas molecules move from regions of higher partial pressure to lower partial pressure, driving diffusion. This gradient is the primary factor determining the direction of gas movement in processes like respiration.
Video consigliato:
6:12
Partial Pressure

Solubility in Water

Solubility in water describes how well a gas dissolves in a liquid, such as blood or water. While it affects the amount of gas that can be carried or absorbed, it does not determine the direction of gas movement, which depends on pressure differences.
Video consigliato:
Percorso guidato
01:54
Introduction to Water

Molecular Weight and Size of Gas Molecules

Molecular weight and size influence the rate at which gas molecules diffuse, with smaller and lighter molecules generally diffusing faster. However, these factors do not dictate the direction of gas movement, which is governed by partial pressure gradients.
Video consigliato:
Percorso guidato
7:17
Classes of MHC Molecules