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How do aortic bodies differ from carotid bodies in their responses to oxygen and carbon dioxide?

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A pine grosbeak with pink and gray plumage perches on a branch, eating red berries among autumn foliage. — Chemoreception Animals, such as this pine grosbeak, use chemoreception to respond to chemicals that can be tasted and smelled in their environments. Many of these chemicals affect behaviors such as food preference and defense.

Both the carotid bodies and aortic bodies function as peripheral chemoreceptors that detect changes in arterial blood chemistry, but they differ in their sensitivity and primary physiological roles.1

Oxygen Response: Both organs respond to acute changes in the partial pressure of oxygen (hypoxia). However, the carotid bodies are the principal arterial chemoreceptors for sensing oxygen levels, while the aortic bodies are primarily responsible for mediating many of the cardiovascular effects associated with hypoxia.1
Carbon Dioxide Response: The carotid bodies are highly sensitive to changes in the partial pressure of carbon dioxide, increasing their activity linearly as levels rise. In contrast, the aortic bodies respond to changes in carbon dioxide much less effectively than the carotid bodies do.1

While both sets of receptors project to the medulla oblongata to help regulate respiration and cardiac output, the carotid body is the more sensitive and versatile sensor for monitoring both oxygen and carbon dioxide fluctuations in the blood.12