LeBlanc 2

Question 1

T/F The RV & LV have the same pressure.

Answer 1

False. The left pressure has much higher pressure than the right side.

Question 2

You get more elastic & less muscular w/ arteries the larger/smaller you get?

Answer 2

Larger Arteries: more elastic

Smaller Arteries: more muscular

Question 3

What do endothelial cells do in arteries?

Answer 3

All blood vessels have a layer of endothelial cells.
Thru NO endothelial causes vasodilation.
If undamaged, endothelial cells keep clots from forming.

Question 4

You need a pressure difference for blood to flow. For this reason RA has low/high BP?
For this reason capillaries have low/high BP?

Answer 4

RA has a low BP so the venous return is possible.

Capillaries also have low BP.

Question 5

What is responsible for the low BP in capillaries?

Why is this important?

Answer 5

Important b/c need time for exchange of gases & nutrients @ the capillary beds.
LOW BP b/c branching & large cross-sectional area
sorta acting against this is the decreased diameter which increasing peripheral resistance.

Question 6

What is the relationship b/w cross sectional area & velocity?

Answer 6

Higher cross sectional area

slower velocity…Think A1v1=A2v2

Question 7

Where is most of the blood held in the vasculature?

Answer 7

2/3 of the blood is held in the veins. Can be constricted out if more cardiac output is needed.

Question 8

Are the right side & left side of the heart are connected in series or in a parallel circuit?

Answer 8

In series.

Question 9

The systemic pathway is connected in series or in parallel?

Answer 9

In parallel.

Question 10

Can veins collapse? When?

Answer 10

Yes, when there is super low pressure, like when there is negative pressure in the chest.

Question 11

Where does the greatest drop in pressure come in the cardiovascular system?

Answer 11

Once you hit the small arteries & arterioles.

Question 12

What is the normal pressure of the RA?

Answer 12

0 mmHg

Question 13

Increased resistance is caused by what change to the blood vessel lumen diameter?

Answer 13

A decrease in the diameter of the lumen of the blood vessel

Question 14

What is the cardiovascular version of V=IR?

Answer 14

BP=Blood Flow X Peripheral Resistance

Question 15

What is the difference b/w pulsatile & continuous flow?

Answer 15

Pulsatile: rhythmically intermittent…b/c of nature of the heart.
Continuous: one long stream

Question 16

Where is there the most pulsatile flow? Continuous Flow?

Answer 16

Most pulsatile flow nearest the heart…nearest the great vessels. Most continuous flow near the capillaries.

Question 17

What are the factors that contribute to the continuous flow near the cardiovascular system?

Answer 17

The big arteries are elastic. If they were stiff, would be more pulsatile.
The resistance of the smaller arteries, arterioles, & capillaries forces continuity.

Question 18

T/F The velocity of blood flow in slower in the SVC & IVC than it is in the aorta.

Answer 18

False. a difference in these velocities would for some reason create an imbalance.

Question 19

Where is the largest reserve of blood in your body?

Answer 19

2/3 of your blood is stored in your veins. If you need more blood in your system…vasoconstriction of the veins & get that stuff moving!

Question 20

What is so special about the atrial kick?

Answer 20

It is an extra contraction of the atrium. It ejects a little extra blood into the ventricle. Thru the Starling mechanism…it causes more ventricular stretching & therefore a stronger contraction.

Question 21

In the Wiggers Diagram…what does the P wave correspond to?

Answer 21

Atrial depolarization.
Atrial contraction--eventually atrial kick
Increased Atrial Pressure
Increase in Ventricular Volume
Slight Increase in Ventricular Pressure

Question 22

When do the AV valves close? What heart sound does this correspond to?

Answer 22

When ventricular pressure is higher than the atrial pressure. S1.

Question 23

What happens after the AV valves close?

Answer 23

Isovolumic contraction.
Ventricular pressure increases dramatically.
Ventricular Volume stays constant.
Atrial pressure increases slightly b/c of transient notch (ventricle pushing up on the atrium)

Question 24

What happens when isovolumic contraction is finished?

Answer 24

Aortic valve opens b/c ventricular pressure is greater than aortic pressure.
Ejection of blood from the ventricle.

Question 25

During ejection what is the relationship b/w the aortic & ventricular pressures?

Answer 25

They are approximately equal.

Question 26

What does the QRS complex relate to?

Answer 26

Ventricular Depolarization
Ventricular Contraction
Eventually ventricular ejection of blood.

Question 27

When does the aortic valve close?

Answer 27

A little after ventricular pressure is lower than aortic pressure…kinetic flow of fluid across the aorta keeps it open a little longer…

Question 28

What does the second heart sound correspond to?

Answer 28

The closure of the semilunar valves. Aortic & pulmonic.

Question 29

What happens after the aortic valve closes?

Answer 29

Isovolumic relaxation.
Ventricular pressure decreases
Ventricular volume stays the same.

Question 30

What does the T wave correspond to?

Answer 30

Ventricular Repolarization.

The ventricle relaxes.

Question 31

What does the 3rd heart sound correspond to?

Answer 31

Ventricular filling during diastole.

Shouldn’t usu hear it–associated w/ heart failure.

Question 32

What is S4?

Answer 32

The 4th heart sound corresponds to the atrial kick against a stiffened, hypertrophied ventricle.

Question 33

What does a refer to in the wiggers diagram?

Answer 33

Atrial contraction

Question 34

What does c refer to in the Wiggers diagram?

Answer 34

Transient notch (sudden increase in atrial pressure b/c of the intense contraction of the ventricle up against it.

Question 35

What does v refer to in the WIggers diagram?

Answer 35

Atrial filling, i think.