Final answer:
Baroreceptors are stretch receptors located in the aortic sinus and carotid bodies. They monitor blood pressure and physical activity. The rate of baroreceptor firing is used to regulate cardiac homeostasis through the baroreceptor reflex.
Step-by-step explanation:
Baroreceptors are stretch receptors located in the aortic sinus and carotid bodies. They monitor blood pressure, physical activity, and blood distribution in the body. The cardiac centers use the rate of baroreceptor firing to maintain cardiac homeostasis through the baroreceptor reflex. When pressure increases, baroreceptor firing increases and the sympathetic stimulation decreases. On the other hand, when pressure decreases, baroreceptor firing decreases and parasympathetic stimulation increases.