Why do you think blood vessel radius can have a larger effect on the body than changes in blood vessel length use the blood flow equation?
Explain why you think blood vessel radius can have a larger effect on the body than changes in blood vessel length (use the blood flow equation). Your answer: Because blood vessel radius change allows for less ressistance which provides greater blood flow.
What happens when blood vessel length increases?
The length of a vessel is directly proportional to its resistance: the longer the vessel, the greater the resistance and the lower the flow. As with blood volume, this makes intuitive sense, since the increased surface area of the vessel will impede the flow of blood.
How does changing the radius affect blood flow?
Therefore, blood flow is strongly proportional to the vessel radius. As the radius of the vessel lumen increases (called vasodilation), blood flow increases dramatically, and vice versa (1).
What is the relationship between blood vessel length?
Blood vessel length is directly proportional to resistance and inversely proportional to blood flow.
What is the relationship between a change in the radius of a vessel and the flow volume through that vessel?
This relationship indicates that at a constant vessel radius, changes in flow are proportionate to changes in velocity, and visa versa. Another important relationship to be derived from above is that velocity, at constant flow, is inversely related to the radius squared (V ∝ 1 / r2 at constant flow).
How does vessel diameter affect blood flow?
In blood vessels, most of the resistance is due to vessel diameter. As vessel diameter decreases, the resistance increases and blood flow decreases. Very little pressure remains by the time blood leaves the capillaries and enters the venules.
What happens to blood flow when the vessel radius decreases?
It is important to note that a small change in vessel radius will have a very large influence (4th power) on its resistance to flow; e.g., decreasing vessel diameter by 50% will increase its resistance to flow by approximately 16 fold. Importantly, flow will only occur when a pressure difference exists.
How does vessel length affect blood pressure?
The longer the total vessel length, the greater the resistance encountered, and the greater the blood pressure. Blood volume affects blood pressure. When there is a greater volume of fluid, more fluid presses against the walls of the arteries resulting in a greater pressure.
How does the body increase the blood vessel radius?
You correctly answered: pressure gradient. How does the body increase the blood vessel radius? You correctly answered: smooth muscle relaxation.
What causes radius to change vessels?
The reason for this is that vessel diameter changes because of contraction and relaxation of the vascular smooth muscle in the wall of the blood vessel. Furthermore, as described below, very small changes in vessel diameter lead to large changes in resistance.