When a person rises quickly from a sitting position, reflex vasoconstriction of peripheral blood vessels occurs. the carotid baroreceptors become less active. Similarly, it is asked, what vessels hold the largest percentage of blood supply?
ANSWER: valves in the veins preventing the backward flow of blood.
Also, what happens when carotid and aortic baroreceptors slow their discharge? When carotid and aortic baroreceptors slow their discharge, ANSWER: the heart rate will decrease to lower blood pressure.
Beside above, which vein is often used to collect blood from an individual?
The antecubital area of the arm is usually the first choice for routine venipuncture. This area contains the three vessels primarily used by the phlebotomist to obtain venous blood specimens: the median cubital, the cephalic and the basilic veins.
What controls the blood flow in and out?
Blood is prevented from flowing backward in the veins by one-way valves. Blood flow through the capillary beds is controlled by precapillary sphincters to increase and decrease flow depending on the body's needs and is directed by nerve and hormone signals.
Related Question Answers
Why does our blood pressure generally go up as we age?
The increase in blood pressure with age is mostly associated with structural changes in the arteries and especially with large artery stiffness. It is known from various studies that rising blood pressure is associated with increased cardiovascular risk. Why is blood flow to the brain relatively continuous and constant?
In a normal physiological state, total blood flow to the brain is remarkably constant due in part to the prominent contribution of large arteries to vascular resistance [58] (see Segmental Vascular Resistance). Why are valves located in veins but not in arteries?
Veins carry the blood back to the heart. Unlike arteries, veins contain valves that ensure blood flows in only one direction. (Arteries don't require valves because pressure from the heart is so strong that blood is only able to flow in one direction.) Which of the following would cause an increase in venous return?
The left ventricle experiences an increase in pulmonary venous return, which in turn increases left ventricular preload and stroke volume by the Frank–Starling mechanism. In this way, an increase in venous return can lead to a matched increase in cardiac output. Which organ secretes Most of the plasma proteins?
liver
Under what general conditions would fluid move into a capillary?
Under what general conditions would fluid move into a capillary? When blood colloid osmotic pressure is greater than capillary hydrostatic pressure. During which phase of contraction is blood pressure highest?
Throughout the cardiac cycle, the arterial blood pressure increases during the phases of active ventricular contraction and decreases during ventricular filling and atrial systole. Thus, there are two types of measurable blood pressure: systolic during contraction and diastolic during relaxation. What happens to the speed of blood as it flows through capillaries?
The rate, or velocity, of blood flow varies inversely with the total cross-sectional area of the blood vessels. As the total cross-sectional area of the vessels increases, the velocity of flow decreases. Blood flow is slowest in the capillaries, which allows time for exchange of gases and nutrients. Why is venous blood used in most Test?
Venous blood is a good indicator of the physiological conditions throughout the body. It is also relatively easy to obtain. Therefore, venous blood is used most frequently for testing. Be sure to collect the specimen in the correct blood tube. What is the difference between venous and capillary blood?
Venous blood (deoxygenated blood) is circulated and pumped through the peripheral blood vessels. The blood then travels through the venous system into the right atrium of the heart. Capillary blood is not identical to venous blood or arterial blood. What may occur if the needle is removed from the arm before removing the tourniquet?
What may occur if the needle is removed from the arm before removing the tourniquet? Bleeding may occur around th puncture site. What may cause a result in hemolysis of the blood specimen? Using a needle with a small lumen to collect the specimen. What is the circulatory route that runs from the digestive tract to the liver called?
The hepatic portal system is a network of veins that bring blood into the capillaries of the liver from the capillaries of the stomach, What are the afferent vessels that carry blood back to the heart?
The afferent vessels that carry blood back toward the heart are d) veins. The afferent vessels are those which carry the oxygen poor blood back to the heart and include the veins and venules, The efferent vessels are those which carry oxygen rich blood away from the heart and that includes the arteries and arterioles. What does blood venous mean?
Venous blood is deoxygenated blood that flows from tiny capillary blood vessels within the tissues into progressively larger veins to the right side of the heart. Venous blood is the specimen of choice for most routine laboratory tests. What causes blood pooling?
Chronic venous insufficiency occurs when your leg veins don't allow blood to flow back up to your heart. Normally, the valves in your veins make sure that blood flows toward your heart. But when these valves don't work well, blood can also flow backwards. This can cause blood to collect (pool) in your legs. What is the path of blood flow from the heart to the lung tissues and back to the heart?
The right ventricle pumps the oxygen-poor blood to the lungs through the pulmonary valve. The left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle through the mitral valve. The left ventricle pumps the oxygen-rich blood through the aortic valve out to the rest of the body. What is the largest artery in the body?
All arteries of the systemic circulation branch from the aorta (this is the largest artery of the body, with a diameter of 2-3 cm), and divide into progressively smaller vessels. What are Baroreceptors sensitive to?
Baroreceptors are sensitive to the rate of pressure change as well as to the steady or mean pressure. Therefore, at a given mean arterial pressure, decreasing the pulse pressure (systolic minus diastolic pressure) decreases the baroreceptor firing rate. When arterial blood pressure decreases Baroreceptors cause a response that?
At normal resting blood pressures, baroreceptors discharge with each heart beat. If blood pressure falls, such as on orthostatic hypotension or in hypovolaemic shock, baroreceptor firing rate decreases and baroreceptor reflexes act to help restore blood pressure by increasing heart rate. Where are Baroreceptors found?
Baroreceptors are mechanoreceptors located in the carotid sinus and in the aortic arch. Their function is to sense pressure changes by responding to change in the tension of the arterial wall. The baroreflex mechanism is a fast response to changes in blood pressure. What are Baroreceptors?
Baroreceptors are a type of mechanoreceptor allowing for the relay of information derived from blood pressure within the autonomic nervous system. Information is then passed in rapid sequence to alter the total peripheral resistance and cardiac output maintaining blood pressure within a preset, normalized range. What is the aortic reflex?
a fall in blood pressure due to peripheral vasodilation and cardiac inhibition by stimulations of terminations of a cardiac depressor nerve in the aortic arch and base of the heart. Which of the following vessels has the lowest blood pressure?
veins
Are Baroreceptors tonic or phasic?
Baroreceptors do not just respond to the static level of blood pressure but they also respond to changes in pressure. These are their phasic properties. If blood pressure abruptly increases, baroreceptors initially give rise to a high frequency of nerve impulses, but then this declines to a lower, steady level. Which of the following cardiovascular changes occur at birth?
Which of the following cardiovascular changes occur at birth? Due to pressure increasing in the left atrium, the foramen ovale closes. With the infant's first breath, the pulmonary vessels expand. When the net filtration pressure is negative what process is occurring?
When the net filtration pressure is negative, what process is occurring? Fluid is moving back into the capillary. 
