PEX 05 03

Exercise 5: Cardiovascular Dynamics: Activity 3: Studying the Effect of Blood Vessel Length on Blood Flow Rate Lab Report
Pre-lab Quiz Results
You scored 100% by answering 4 out of 4 questions correctly.
1. When the length of the blood vessel increases, which of the following also increases?
You correctly answered: d. both friction and surface area
2. Blood vessel length decreases
You correctly answered: c. when we lose weight.
3. Blood flow is
You correctly answered: b. directly proportional to vessel radius to the fourth power.
4. Which of the following correctly describes resistance to flow?
You correctly answered: a. Resistance to flow increases with increased vessel length.

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Experiment Results
Predict Question:
Predict Question: What effect do you think increasing the flow tube length will have on the fluid flow rate?
Your answer : c. The fluid flow rate will decrease.
Stop & Think Questions:
What is the relationship between fluid flow and flow tube length?
You correctly answered: b. They are inversely proportional to each other.
Which is more likely to occur on a daily basis?
You correctly answered: b. changes in blood vessel diameter
Experiment Data:
Flow (ml/min)
90.8
60.6
45.4
36.3
30.3
26.0
22.7

Radius (mm)
3.0
3.0
3.0
3.0
3.0
3.0
3.0

Viscosity
3.5
3.5
3.5
3.5
3.5
3.5
3.5

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Length (mm)
10
15
20
25
30
35
40

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Pressure (mm Hg)
100
100
100
100
100
100
100

Post-lab Quiz Results
You scored 100% by answering 4 out of 4 questions correctly.
1. Increasing the flow tube length is analogous to increasing blood vessel length. How did this affect the flow rate?
You correctly answered: b. The flow rate decreased.
2. Which of the following correctly describes the relationships between blood vessel length, resistance, and blood flow?
You correctly answered: c. Blood vessel length is directly proportional to resistance and inversely proportional to blood flow.
3. Which of the following correctly describes the relationships between