Carbon dioxide is transported from tissues to respiratory surface by only

Explanation

All options are explained below: a) plasma and erythrocytes : In this option, it is suggested that carbon dioxide is transported from tissues to the respiratory surface by both plasma (the liquid component of blood) and erythrocytes (red blood cells). While plasma can carry some dissolved CO2, it is not the primary mechanism for CO2 transport. Erythrocytes play a significant role in carrying CO2, especially in the form of bicarbonate ion. In short:While plasma can carry some dissolved carbon dioxide, the primary mechanism for transporting CO2 from tissues to the respiratory surface is via erythrocytes (red blood cells), where CO2 is converted into bicarbonate ions. Both plasma and erythrocytes are involved in CO2 transport, but erythrocytes play a more central role in this process. Please note that in the typical understanding of respiratory physiology, erythrocytes are considered the primary carriers of CO2, which is converted into bicarbonate ions. Plasma carries some dissolved CO2, but it is not the primary method of CO2 transport. b) Plasma: Plasma is the liquid component of blood and can carry some dissolved carbon dioxide (CO2). However, this is not the primary mechanism for CO2 transport. While plasma can hold a portion of the dissolved CO2, the most significant portion of CO2 is transported differently. c) Erythrocytes: The primary mechanism for transporting carbon dioxide from tissues to the respiratory surface is via erythrocytes (red blood cells). Erythrocytes can bind to CO2 and convert it into bicarbonate ions, which can be carried in the blood to the respiratory surface. This is the most important mechanism for CO2 transport in the blood. d) Erythrocytes and Leucocytes:Leukocytes (white blood cells) are primarily involved in the immune system and do not play a significant role in the transport of carbon dioxide. The primary role in CO2 transport is attributed to erythrocytes. Option A is correct. Summary: The primary mechanism for transporting carbon dioxide from tissues to the respiratory surface is through erythrocytes (red blood cells). Erythrocytes can bind to CO2 and convert it into bicarbonate ions, which are carried in the blood to the respiratory surface. While some CO2 can dissolve in the plasma, erythrocytes play the most significant role in CO2 transport in the blood.