CVT 100 #5 PHYSICS WEEK 6 EXAM REVIEW

Question 0

What is the definition of Force

Answer 0

mass x acceleration

Question 1

What is the definition of mass

Answer 1

a quantity of stuff

can be defined by how much force it takes to change its state…

Question 2

What is the definition of Pressure

Answer 2

force per unit area

Question 3

Define Resistance

Answer 3

opposition to movement

Question 4

Definition of Flow

Answer 4

volume per unit time

Question 5

Velocity

Answer 5

distance per unit time

Question 6

Units for force & pressure

SYSTEM: SI

Force:

Pressure:

Answer 6

Force : Newton (kg*m/sec^2)

Pressure: Newtons/m^2

Question 7

Poiseuille’s Law:

• Resistance equation Flow equation •

Answer 7

Expressions of ∆P

P1 - P2 or P1 - P2
———- ———-
Time Length

Question 8

Units for force & pressure

SYSTEM: CGS

Force:

Pressure:

Answer 8

Units for force & pressure

SYSTEM: CGS

Force: dyne (g*cm/sec^2)

Pressure: dynes/cm^2

Question 9

Units for force & pressure

SYSTEM: British

Force:

Pressure:

Answer 9

Units for force & pressure

SYSTEM: British

Force: Slug (slug*ft./sec^2)

Pressure: lb./inch^2

Question 10

Two ways to increase blood flow from heart during exercise:

Answer 10

1. Increase heart rate

2. Increase force of myocardial contraction

Question 11

Frank-Starling Law:

Answer 11

More filling,
more stretch —> more forcible contraction (more contractile force)

Balloon analogy: blow up a little, little force; blow up a lot, more force on release.

Or rubber band analogy: pull a little bit, little force; pull a lot, more force.

Question 12

Function in Systole

Open Valves

Closed Valves

Answer 12

Systole Contraction, ejection

Approximately 1/3 of the cardiac cycle

Open valves: Aortic and pulmonic

Closed valves: Mitral and tricuspid

Question 13

Function during Diastole

Open Valves

Closed Valves

Answer 13

Diastole Relaxation

Approximately 2/3 of the cardiac cycle

Open valves: MV and TV

Closed valves: AoV and PV

Question 14

Distribution of blood volume:

Answer 14

About 1/3 in the arterial side,

and about 2/3 in the venous side.

Question 15

Right heart provides energy for the

Answer 15

pulmonary circulation.

Question 16

Left heart provides energy for the

Answer 16

systemic circulation.

Question 17

The net effect of exercise is usually an increase of

Answer 17

systemic blood pressure.

Question 18

What is acceleration?

Answer 18

Change of speed and/or direction.

Strictly speaking, velocity implies both speed and direction.

Question 19

Converting mmHg to dynes/cm2

Answer 19

1 mmHg = 1333 dynes/cm2

( it’s okay for our purposes to use 1.3 x 103)

So, 120 mmHg = ________ dynes/cm2

Question 20

To change dynes/cm2 to mmHg

Answer 20

DIVIDE by (1.3 x 10^3)

Question 21

Starling’s Law

Answer 21

Increased LV filling,

increased myocardial stretch,

increased force of contraction

Question 22

Exercise physiology:

•Muscle contraction —>

Answer 22

collapse veins More blood goes to heart and arterial side
•More force of contraction (Starling) —> higher BP

More blood from heart due to:

a) stronger contractions, and
b) increased heart rate

Question 23

Arterioles dilate in response to

Answer 23

local chemistry (metabolites) —> decreased resistance in muscles —> more flow to muscles

Question 25

Viscosity

Answer 25

``` "is the measure of a fluids resistance to flow and deformation due to stress Common symbol(s): η, μ ``` SI unit: Pa·s = kg/(s·m)

Question 26

Pressure drops across segments of circulation.

Answer 26

* 1st Arteries - Aorta - Large arteries - Branch arteries * 2nd Arterioles * 3rd Capillaries * 4th Venules and veins

Question 27

2/3 to 3/4 of the blood is in our ...

Answer 27

venous cycle because it needs to go back to the heart for SaO2.

Question 28

arterioles control the flow of the system because they control ...

Answer 28

the diameter by adjusting the resistance. When the arterioles are contracted they are constricting the flow and when they are relaxed they dilate the vessels.

Question 29

The largest drop is in the____________because...

Answer 29

The largest drop is in the ARTERIOLES | BECAUSE: they control the flow by constricting and dilating the vessels.

Question 30

Force/pressure/area Flow/∆P/resistance Don’t forget conversion factors for: ---------------------------------------- mmHg to/from dynes/cm2 and L/min to/from cm3/sec

Answer 30

Force/pressure/area Flow/∆P/resistance Don’t forget conversion factors for: ---------------------------------------- mmHg to/from dynes/cm2 and L/min to/from cm3/sec

Question 31

Expressions of ∆P •

Answer 31

P1 - P2 or P1 - P2 ---------- ---------- Time Length

Question 32

WHAT HEART VALVES ARE OPEN DURING SYSTOLE?

Answer 32

AO AND PV | AORTIC VALVE AND PULMONARY VALVE

Question 33

WHICH VALVES ARE OPEN DURING DIASTOLE?

Answer 33

MV AND TV | Mitral valve and Tricuspid Valve

Question 34

``` CHARACTERISTICS OF VESSELS: ARTERIES: Velocity Pressure Resistance Volume ```

Answer 34

``` ARTERIES HAVE: HIGHEST VELOCITY HIGHEST PRESSURE LOW TO MODERATE RESISTANCE ~12% VOLUME ```

Question 35

``` CHARACTERISTICS OF VESSELS: ARTERIOLES: Velocity Pressure Resistance Volume ```

Answer 35

``` ARTERIOLES HAVE: LOWER VELOCITY LOWER PRESSURE HIGHEST RESISTANCE ~2% VOLUME ```

Question 36

``` CHARACTERISTICS OF VESSELS: CAPILLARIES: Velocity Pressure Resistance Volume ```

Answer 36

``` CAPILLARIES HAVE: LOWEST VELOCITY LOWER PRESSURE LOW TO MODERATE RESISTANCE ~5% VOLUME ```

Question 37

``` CHARACTERISTICS OF VESSELS: VEINS: Velocity Pressure Resistance Volume ```

Answer 37

``` VEINS HAVE: VELOCITY UP AGAIN LOWEST PRESSURE LOWEST RESISTANCE ~2/3 VOLUME ```

Question 38

When would you measure AORTIC STENOSIS? Where would you measure?

Answer 38

MEASURE VELOCITY AT SYSTOLE MEASURE PRESSURE IN THE LV AND AO INCREASED PRESSURE IN THE LV

Question 39

When would you measure MV STENOSIS? Where would you measure?

Answer 39

MEASURE VELOCITY AT DIASTOLE MEASURE PRESSURE IN THE LA AND LV INCREASED PRESSURE IN THE LA

Question 40

Sx of LE arterial obstructive disease Claudication:

Answer 40

pain with exercise, relieved by rest Usually calf, possibly progressing to thigh, hip, buttock

Question 41

WHENEVER YOU HAVE A NARROWING/STENOSIS, YOU HAVE A LOSS OF ENERGY WHERE?

Answer 41

DISTAL TO THAT STENOSIS.

Question 42

WHEN WOULD YOU ASSESS FOR AN AORTIC STENOSIS?

Answer 42

DURING SYSTOLE

Question 43

WHERE WOULD I FIND THE HIGHER PRESSURE?

Answer 43

IN THE LV

Question 44

WHEN WOULD YOU ASSES FOR MITRAL VALVE STENOSIS?

Answer 44

DURING DIASTOLE

Question 45

WHERE WOULD YOU FIND THE HIGHER PRESSURE?

Answer 45

IN THE LA

Question 46

WHAT DOES A SIGNIFICANT GRADIENT BETWEEN THE CUFFS SUGGEST?

Answer 46

THAT THERE IS SOME STENOSIS BETWEEN THE CUFFS.