Question

Carbon dioxide is carried from the tissues to the lungs by a variety of mechanisms. Which of the following lists these mechanisms in order representing the mechanism that carries the most carbon dioxide to the mechanism that carries the smallest amount?
bicarbonate-carbaminohemoglobin-dissolved in plasmadissolved in plasma-bicarbonate-carbaminohemoglobinbicarbonate-dissolved in plasma-carbaminohemoglobincarbaminohemoglobin-bicarbonate-dissolved in plasma

Answer 1

Answer:

bicarbonate-carbaminohemoglobin-dissolved in plasma

Explanation:

Transport of CO2 in the blood occurs in three main forms. Most of the CO2 is carried in the blood as bicarbonate. It accounts for transport of about 70% CO2. In RBCs, CO2 reacts with water in the presence of the enzyme carbonic anhydrase to form carbonic acid, which dissociates into H+ and HCO3-. Bicarbonate formation also occurs in blood plasma.

About 23% of CO2 is carried in the form of carbamino-compounds. Binding of CO2 to hemoglobin forms carbaminohemoglobin. The smallest percentage of CO2 (about 7%) is dissolved in blood plasma and is diffused into the alveolar air as it reaches the lungs.