Kyle McTeigue
Physioex 5
Act. 1 Effect of Blood Vessel Radius on Blood Flow Rate
1. Discuss the effect of changing the flow tube radius on flow rate.
● I observed the rate of flow increases with radius size
2. Describe the effect of changing the flow tube radius on laminar flow of a fluid. How is this
critical to our human blood flow?
● Increasing the diameter increased the flow, it allows us to control blood flow by
constricting or dilating our vessels
3. Why is the relationship exponential between radius and blood flow rate?
● Even little changes in the diameter can affect the flow
Act. 2 Effect of Blood Viscosity on Blood Flow Rate
1. List blood components that affect blood viscosity; identify specific situations when viscosity
would change (positive and negative).
● Hematocrit
● Exercise, Dehydration, Inflammation,Temperature, Meds
2. Discuss the effect that the lab’s viscosity changes had on flow rate.
● More power the more slowed
Act. 3 Effect of Blood Vessel Length on Blood Flow Rate
1. Discuss the amount of time it takes for a change in blood vessel length and blood vessel
radius. When would each occur?
● Length Takes longest Diameter happens quickly
2. Describe the effect of a change in blood vessel length on flow rate in the experiment.
● Length increases flow rate slows heart has to pump farther same as fire hoses.
3. How would obesity affect the flow rate? Why? How would diabetes affect flow rate? Why?
● Both would Slow it down due to being heart not able to pump as hard through the
vessels due to the fatty deposits
Act. 4 Effect of Blood Pressure on Blood Flow Rate
1. Describe the effect of pressure changes on blood flow rate from the experiment.
● Higher the pressure, increased rate
2. Explain why pressure changes are not the best way to control blood flow. What are
potential problems with pressure changes in the CV system?
● To much stress on the heart
Act. 5 Effect of Blood Vessel Radius on Pump Activity
1. Explain the effect of increasing the right flow tube radius on the flow rate, resistance and
pump rate.
● Larger the diameter = less resistance
More Flow = slower the pump rate
2. In the Experiment, what human heart volumes do the right and left beakers represent.
● Amount of blood in the right and left ventricles
Act. 6 Effect of the Stroke Volume of the Pump Activity
1. What is the Frank-Starling law in the heart? Why is it important?
● Stroke volume increases in response to preload. It helps regulate cardiac output
2. What happens to the pump rate when stroke volume is decreased? When will it is increased?
● Heart rate increases stroke volume decreases
3. How does the heart alter stroke volume?
● Preload contractility and afterload
Act. 7 Pathological Cardiovascular Conditions & Compensation
1. How does the heart compensate for changes in peripheral resistance?
● Heart rate and stroke volume
. During the experiment, what happens when the pump pressure and beaker pressure are the
same?
● No net movement of water
3. According to cardiovascular system effects, would it be better to adjust heart rate or blood
vessel diameter to increase blood flow to an injured extremity?
● Blood vessel diameter