What is the sensor in the baroreceptor reflex?
Sensors for the reflex detect blood pressure at two sites in the upper part of the body: the aortic arch, just above the heart, and the carotid sinus, in the neck where the carotid artery bifurcates before heading to the brain.
What are the components of the baroreceptor reflex?
The components of the reflex arc responsible for the short-term blood pressure regulation are: 1) receptor endings of afferent fibers located in the adventitia of the carotid sinus and aortic arch and running along branches of the glosso-pharyngeal and vagus nerves, respectively; 2) central integrative sites.
What are arterial baroreceptors?
The arterial baroreceptors are mechanoreceptors located in the carotid sinuses (innervated by the glossopharyngeal nerve, IX) and aortic arch (innervated by the vagus nerve, X) that respond to stretch elicited by increase in arterial pressure.
Why is the baroreceptor reflex important?
The baroreflex or baroreceptor reflex is one of the body’s homeostatic mechanisms that helps to maintain blood pressure at nearly constant levels. Decreased blood pressure decreases baroreflex activation and causes heart rate to increase and to restore blood pressure levels.
Where are the sensors for the arterial baroreceptor reflex located?
52 Cards in this Set
| Where are the sensors for the arterial baroreceptor reflex located? | carotid sinus and aortic arch |
|---|---|
| In the capillaries, hydrostatic pressure (HP) is exerted by __________. | blood pressure |
What is the purpose of the baroreceptor reflex?
The baroreflex or baroreceptor reflex is one of the body’s homeostatic mechanisms that helps to maintain blood pressure at nearly constant levels.
What triggers baroreceptor reflex?
Activation. The baroreceptors are stretch-sensitive mechanoreceptors. At low pressures, baroreceptors become inactive. When blood pressure rises, the carotid and aortic sinuses are distended further, resulting in increased stretch and, therefore, a greater degree of activation of the baroreceptors.
Why does the body have arterial baroreceptors?
Arterial baroreceptors control the sympathetic drive to the heart and the peripheral blood vessels. They constantly adjust the sympathetic activity in relation to systemic blood pressure changes in order to maintain homeostasis.
What is the site where resistance to blood flow is greatest?
arterioles
Part (c) shows that blood pressure drops unevenly as blood travels from arteries to arterioles, capillaries, venules, and veins, and encounters greater resistance. However, the site of the most precipitous drop, and the site of greatest resistance, is the arterioles.
How does the baroreceptor reflex regulate arterial pressure?
Under normal conditions, arterial pressure is maintained within very narrow limits, and this regulation is accomplished by a powerful negative feedback reflex, the baroreceptor reflex.
Where are the baroreceptors located in the cardiovascular system?
Arterial Baroreceptors. The most important arterial baroreceptors are located in the carotid sinus (at the bifurcation of external and internal carotids) and in the aortic arch (Figure 1). These receptors respond to stretching of the arterial wall so that if arterial pressure suddenly rises, the walls of these vessels passively expand,…
Why are baroreceptors important to the autonomic nervous system?
Arterial baroreceptors function to inform the autonomic nervous system of beat-to-beat changes in blood pressure within the arterial system.
Why does blood pressure decrease baroreceptor firing rate?
Arterial Baroreceptors. Therefore, at a given mean arterial pressure, decreasing the pulse pressure (systolic minus diastolic pressure) decreases the baroreceptor firing rate. This is important during conditions such as hemorrhagic shock in which pulse pressure as well as mean pressure decreases.