Question

most of the carbon dioxide you exhale comes from which of the following?

Multiple choice question.

CO2 carried in the plasma as dissolved gas


Bicarbonate ions transported into the RBCs and used to generate free CO2.


CO2 released from carbaminohemoglobin in the erythrocytes


CO2 released from carbamino compounds in the plasma

Answers

GPT-4o mini
Most of the carbon dioxide you exhale comes from **bicarbonate ions transported into the RBCs and used to generate free CO2**.

In the body, carbon dioxide is primarily transported in three forms: dissolved CO2 in plasma, bicarbonate ions (HCO3-) in plasma, and carbamino compounds. The majority of CO2 is converted to bicarbonate ions, predominantly in red blood cells (RBCs). When needed, bicarbonate can be converted back to CO2, which is then exhaled through the lungs.