Why does pressure drop increase with flow rate?
Under laminar flow conditions, pressure drop is proportional to volumetric flow rate. At double the flow rate, there is double the pressure drop. Since increasing the temperature of the gas increases its viscosity, pressure drop also increases as gas temperature increases.
Why does blood pressure decrease as blood flows from the arteries to the capillaries?
Arterioles have the most increase in resistance and cause the largest decrease in blood pressure. The constriction of arterioles increases resistance, which causes a decrease in blood flow to downstream capillaries and a larger decrease in blood pressure.
Why does vasoconstriction increase BP?
Vasoconstriction and blood pressure Vasoconstriction reduces the volume or space inside affected blood vessels. When blood vessel volume is lowered, blood flow is also reduced. At the same time, the resistance or force of blood flow is raised. This causes higher blood pressure.
How does pressure affect blood flow?
If you increase pressure in the arteries (afterload), and cardiac function does not compensate, blood flow will actually decrease. In the venous system, the opposite relationship is true. Increased pressure in the veins does not decrease flow as it does in arteries, but actually increases flow.
Which organ has maximum blood flow at rest?
The hepatic portal system is the system of veins comprising the hepatic portal vein and its tributaries. The liver consumes about 20% of total body oxygen when at rest, so the total liver blood flow is quite high.
Which blood vessels experience the sharpest decrease in blood pressure?
The greatest drop in blood pressure occurs at the transition from arteries to arterioles. Primary function of each type of blood vessel: Arterioles have a very small diameter (<0.5 mm), a small lumen, and a relatively thick tunica media that is composed almost entirely of smooth muscle, with little elastic tissue.