Final answer:
Hypercapnia is characterized by abnormally high levels of carbon dioxide in the blood, typically due to impaired respiratory function or hypoventilation. The transport of CO2 in the blood involves carbonic anhydrase and can lead to serious health issues if not managed properly.
Step-by-step explanation:
Hypercapnia refers to elevated levels of carbon dioxide (CO2) in the blood. This condition can occur due to respiratory dysfunction caused by diseases like pneumonia and congestive heart failure or as a result of hypoventilation. Hypoventilation can be induced by certain drugs, or voluntarily by holding one's breath. On the contrary, hypocapnia denotes abnormally low levels of CO2, often due to hyperventilation, which can occur under various conditions including salicylate toxicity or fever.
When it comes to CO2 transport in the blood, it can be carried in three ways: dissolved directly in the plasma, bound to hemoglobin as carbaminohemoglobin, or most commonly converted to bicarbonate ions by the enzyme carbonic anhydrase in erythrocytes. The understanding of these processes is crucial for managing the effects and treatment of hypercapnia, and distinguishes it clearly from other conditions like hypercalcemia and hyperchloremia.