Gas Transport and Control of Respiration

These flashcards cover the key concepts related to gas transport mechanisms of carbon dioxide and the neural control of respiration.

What are the three ways carbon dioxide (CO2) is transported in the bloodstream?

1. Converted to carbonic acid 2. Bound to hemoglobin within red blood cells 3. Dissolved in plasma.

What percentage of CO2 is transported as bicarbonate ions (HCO3–)?

70%.

What is the process through which bicarbonate ions move into plasma?

In exchange for chloride ions, known as the chloride shift.

What is the role of carbonic anhydrase in gas transport?

It catalyzes the reaction converting water and CO2 into carbonic acid.

What is the primary function of the ventral respiratory group (VRG)?

It regulates both inspiratory and expiratory functions during forced breathing.

What is the reflex action of chemoreceptors in response to increased carbon dioxide levels?

They stimulate increased ventilation to expel more CO2.

What physiological conditions do peripheral chemoreceptors respond to?

Changes in CO2, O2, and pH levels in the blood.

How do central chemoreceptors monitor blood gases?

They respond to changes in pH of cerebrospinal fluid, which correlates with CO2 levels.

What happens to the bicarbonate ions when CO2 diffuses out of the bloodstream in the lungs?

They are pulled back into red blood cells and converted back to CO2.