What is the goal of short term control of the CV system?
Maintain cerebral and coronary blood flow
What is the goal of long term control of the CV system?
Maintain adequate blood flow to all tissues of the body
If blood flow to tissues is inadequate, what can exist?
Shock
Where is the largest volume of blood found?
In venous system in unstressed individual
What contains small volumes of blood?
Arterial system, pulmonary circulation, cardiac circulation and capillary beds
What is meant by blood flow?
Volume of blood which moves through a vessel over time
What is meant by blood velocity?
Distance a component of the blood moves over time (linear displacement over time)
What is meanth by blood pressure?
Force per unit area
The continuity equation is the relationship between what?
Vessel diameter, velocity and flow
What is the continuity equation?
Flow = velocity * area
The flow through a vessel is dependent on the
velocity of blood in the vessel and the cross-sectional area of the vessel
If area increases, what happens to velocity if flow is kept the same?
Decreases
If blood flow through a vessel is constant while its cross sectional area is decreased, what will happen to blood velocity?
Will increase
As you move away from the heart, the total cross sectional area of the vessels increases, so that blood velocity
decreases
When flow is constant, there is an iverse relationship between velocity and
cross sectional area
Blood moves slowly through the capillaries to provide
adequate time for diffusion to occur
What parameters determine blood flow?
Pressure gradient and resistance
Flow = Change in P/R
Less resistance =
more flow
More driving force (pressure) =
More flow
Blood flow through a vessel is directly proportional to the pressure difference __________
across the vessel
Blood flow through a vessel is inversely proportional to the
resistance of the vessel
Resistance is directly proportional to the
length of the vessel
Is the change in length of blood vessels a means for regulation of resistance?
no
Resistance is inversely proportional to the
radius of a vessel to the 4th power