Peripheral chemoreceptors are specialized sensory cells located primarily in the carotid bodies and aortic bodies. They play a crucial role in monitoring the levels of oxygen, carbon dioxide, and pH in the blood. When oxygen levels drop or carbon dioxide levels rise, these receptors send signals to the respiratory center in the brain, prompting an increase in breathing rate to restore balance. These chemoreceptors are essential for maintaining homeostasis, especially during physical activity or in response to environmental changes. By detecting changes in blood chemistry, peripheral chemoreceptors help regulate respiratory function and ensure that the body receives adequate oxygen for its metabolic needs.