Advertisement Upgrade to remove ads

Blood flow is measured in:


Which of the following has the greatest effect on blood flow?

Blood Vessel Radius

Which of the following would NOT result in a decrease in the blood vessel radius?


The diameter of the blood vessel is the same as:

Two times the radius of the blood vessel

The opening of the blood vessel where the blood flows is called the:


What happens to flow rate when the flow tube radius is increased?

The flow rate increases

If radius is plotted on X-axis and flow rate on Y-axis what will the graph look like?

NOT linear; There is an exponential relationship between the variables

What is the driving force for blood flow?

Pressure gradient

How does the body increase the blood vessel radius?

smooth muscle relaxation

Vessel radius and fluid flow are directly or inversely proportional?

directly proportional

After a heavy meal, when we are inactive, blood vessels in the skeletal muscle somewhat _______ and the blood vessels in the digestive organs are ____

constricted; dilated

How does the body establish a pressure gradient for fluid flow?

Due to the pressure difference between the two ends of the vessel

What effect does changing the radius have on the laminar flow of a fluid?

Fully constricted vessels do NOT favor laminar flow because there is more blood in contact with the vessel wall and therefore the blood does not flow as freely

Which of the following is NOT a formed element?

plasma protein

Thrombocytopenia is a reduction in platelets. What effect do you think this could have on blood viscosity?

decrease blood viscosity

Which of the following does NOT contribute to the viscosity of the blood?

oxygen level in the blood

Viscosity most directly affects:

peripheral resistance

What effect does increasing the viscosity have on the fluid flow rate?

decreases the flow rate

What is the relationship between fluid flow and viscosity?

they are inversely proportional

What effect does aplastic anemia (reduced red blood cells) have on blood flow?

increased blood flow due to decreased viscosity

What are the components that affect viscosity?

The formed elements and plasma proteins including leukocytes, erythrocytes, platelets, and proteins such as albumin.

What does the graph of fluid flow v. viscosity look like?

The graph was NOT linear, it was exponential.

What effect does polycythemia have on viscosity and flow?

Polycythemia is an increase in the RBC numbers. This would result in an increase in viscosity and a corresponding decrease in flow.

What effect would a decreased hematocrit have on blood flow?

decreased viscosity; increased flow

What do you predict would be the overall affect on viscosity during dehydration?

increased viscosity; decreased flow

When the length of the blood vessel increases, what characteristic(s) also increase?

Friction AND surface area

Blood vessel length increases or decreases when we lose weight?


Blood fow is directly proportional to what?

Vessel radius raised to the 4th power

Which of the following correctly describes resistance to flow (what is directly proportional)?

Resistance to flow increases with increased vessel length

What is the relationship between fluid flow and flow tube length?

Inversely proportional

What is more likely to occur, a change in blood vessel radius or a change in blood vessel length?

Change in blood vessel diameter occurs daily to accomodate homeostasis

Why does blood vessel radius have a larger effect on the body than changes in vessel length? (use the blood flow equation)

The vessel radius varies to a power of 4 which is why the change is greater than that of vessel length

What effect does obesity have on blood flow and why?

Obesity decreases blood flow due to an increase in blood vessel length generated to serve the increase in adipose.

Describe the relationship between blood vessel LENGTH, resistance, and flow.

Length is directly proportional to resistance and inversely proportional to blood flow.

Describe the relationship between blood vessel RADIUS, resistance, and flow.

Radius is inversely proportional to resistance and directly proportional to blood flow.

Why might a body require an increase in vessel radius?

To provide more blood flow and therefore nutrients to a particular body part

Pressure changes in the cardiovascular system primarily result from;

changes in the force of contraction in the heart

What is the driving force for blood flow?

pressure gradient

Which characteristic(s) is/are directly proportional to blood flow?

blood vessel radius and pressure gradient

Arteries close to the heart need to be able to compensate for:

pressure changes

What effect does increasing the pressure have on flow rate?

increases flow rate

What does a graph look like plotted pressure v. flow rate?

Straight line! The only one!

Pressure changes in the experiment model what in the body?

changes in the force of contraction in the heart

Why are pressure changes not the best way to control blood flow?

Diameter changes are much easier for the body to make. Pressure changes require the heart to beat harder which is difficult for the heart to sustain.

What was the increase in flow rate in ml/min/mm Hg?

1.4 ml/min/mm Hg. Using the equation, divide the flow rate change by the change in pressure

Blood pressure is measured in:

mm Hg

What variable has the greatest effect on blood flow?

vessel radius

The heart is resting during:

ventricular diastole

The right side of the heart pumps blood to?

the lungs

The layer of blood vessel that is stimulated by the ANS is?

smooth muscle

In the experiment, the pump simulates what part of the heart?

the left ventricle of the heart

If the right beaker stimulates the flow of blood to the systemic circuit of the body, what do the right valve and flow tube represent? (part of the heart)

aortic valve and aorta

How does increasing the right flow tube radius affect flow rate, resistance, and pump rate?

as the right flow tube radius is increased, blood flow increases, resistance decreases, and pump rate increases

When the piston of the pump reaches its lowest point, the volume remaining in the pump is the __?

end systolic volume

If you increase the right flow tube radius, what will happen to resistance and flow rate?

the flow rate will increase and resistance will decrease

If the left flow tube represents the pulmonary veins, what does the left source beaker represent? (blood from __)

blood coming from the lungs

Describe what the left and right beakers in the experiment correspond to in the human heart (blood from/to where)

Left beaker stimulates blood FROM the lungs and right beaker is blood traveling TO the systemic circuit.

How can the heart compensate for flow rate changes to maintain constant blood pressure?

if flow rate increases, the heart must pump faster to maintain constant bp

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording