logo

Animation: Transport of Respiratory Gases

by Pearson
1 views
Was this helpful ?
0
Let's start by looking at the movement of respiratory gases between blood and the body's tissue cells. Oxygen molecules are unloaded from hemoglobin, a protein in red blood cells. Oxygen diffuses into the blood plasma, through the capillary wall, into the interstitial fluid, and into cells, where it is used in cellular respiration. As carbon dioxide is produced by cellular respiration in the cells, it diffuses into the interstitial fluid, through the capillary wall, and into the blood plasma. Some CO2 remains dissolved in the plasma, but most enters red blood cells. Some CO2 combines with hemoglobin. Most of the carbon dioxide, however, reacts with water to form carbonic acid (H2CO3). Carbonic acid breaks up to form a hydrogen ion (H+) and a bicarbonate ion (HCO3-). Hemoglobin picks up most of the hydrogen ions, preventing them from making the blood too acidic. The bicarbonate ions diffuse out of the red blood cell into the plasma. Oxygen-poor blood carrying carbon dioxide leaves the tissue capillaries and moves through blood vessels to the heart, where it is pumped to the alveolar capillaries of the lungs. When blood gets to the lungs, hemoglobin gives up its carbon dioxide and hydrogen ions. Bicarbonate combines with hydrogen ions to form carbonic acid, which is then converted back into carbon dioxide and water. Carbon dioxide diffuses out of the cell, out of the blood plasma, and into an alveolus in the lungs, where it is expelled with exhaled air. Meanwhile, oxygen from inhaled air diffuses out of the alveolus, into the blood plasma, and into the red blood cell, where it combines with hemoglobin. Oxygen-rich blood then leaves the alveolar capillaries and travels to the heart, where it is pumped through blood vessels to tissue capillaries. There, red blood cells deliver oxygen to tissue cells.
Let's start by looking at the movement of respiratory gases between blood and the body's tissue cells. Oxygen molecules are unloaded from hemoglobin, a protein in red blood cells. Oxygen diffuses into the blood plasma, through the capillary wall, into the interstitial fluid, and into cells, where it is used in cellular respiration. As carbon dioxide is produced by cellular respiration in the cells, it diffuses into the interstitial fluid, through the capillary wall, and into the blood plasma. Some CO2 remains dissolved in the plasma, but most enters red blood cells. Some CO2 combines with hemoglobin. Most of the carbon dioxide, however, reacts with water to form carbonic acid (H2CO3). Carbonic acid breaks up to form a hydrogen ion (H+) and a bicarbonate ion (HCO3-). Hemoglobin picks up most of the hydrogen ions, preventing them from making the blood too acidic. The bicarbonate ions diffuse out of the red blood cell into the plasma. Oxygen-poor blood carrying carbon dioxide leaves the tissue capillaries and moves through blood vessels to the heart, where it is pumped to the alveolar capillaries of the lungs. When blood gets to the lungs, hemoglobin gives up its carbon dioxide and hydrogen ions. Bicarbonate combines with hydrogen ions to form carbonic acid, which is then converted back into carbon dioxide and water. Carbon dioxide diffuses out of the cell, out of the blood plasma, and into an alveolus in the lungs, where it is expelled with exhaled air. Meanwhile, oxygen from inhaled air diffuses out of the alveolus, into the blood plasma, and into the red blood cell, where it combines with hemoglobin. Oxygen-rich blood then leaves the alveolar capillaries and travels to the heart, where it is pumped through blood vessels to tissue capillaries. There, red blood cells deliver oxygen to tissue cells.