CVT 100 #2 Cardiovascular overview

Question 1

Distribution of blood volume:

Answer 1

About 1/3 in the arterial side,
and
about 2/3 in the venous side.

Question 2

Right heart provides energy for

Answer 2

the pulmonary circulation.

Question 3

Left heart provides energy for

Answer 3

the systemic circulation.

Question 4

Categories of vessels:

Answer 4

Aorta
Arteries
Arterioles
Capillaries
Venules
Veins
Vena Cavae

Question 5

Systole

Answer 5

Contraction, ejection
Approximately 1/3 of the cardiac cycle

Open valves:
Aortic and pulmonic

Closed valves:
Mitral and tricuspid

Question 6

Diastole

Answer 6

Relaxation
Approximately 2/3 of the cardiac cycle

Open valves:
MV and TV

Closed valves:
AoV and PV

Question 7

What is Blood pressure?

Answer 7

Pressure against walls
Represents potential energy
Measured in mmHg
Typical: 120/80 mmHg
(Peak pressure over residual pressure)
This energy created by 
      myocardial contraction

Question 8

Define Blood pressure:

Answer 8

A measurement of
force per unit area

(The energy is actually
mass x acceleration,
but this is difficult to measure.)

Question 9

What happens during exercise?

Answer 9

Muscles compress veins (low-pressure...)
More blood back to heart
Muscles relay demand for O2 to brain
   (Increased heart rate, 
     increased sympathetic activity)

Question 10

Frank-Starling Law:

Answer 10

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 11

Two ways to increase blood flow from heart during exercise:

Answer 11

1. Increase heart rate
2. Increase force of
   myocardial contraction

Question 12

What do Arterioles respond to?

Answer 12

Respond to sympathetic nerve activity
AND to local chemistry (metabolites)
with vasodilatation
(less resistance, more flow)
to deliver more O2 
and carry away waste products

Question 13

Arterioles control flow by controlling…

Answer 13

resistance.

Question 14

The net effect of exercise is usually an increase of

Answer 14

systemic blood pressure.

Question 15

Force ismass x accelerationEquation

*Note that mass is not the same thing as weight—weight is the force of gravityacting on mass.
And “acceleration” in physics is any change of speed, higher or lower, or change of direction.

Answer 15

P = F
A

Also:
F = P x A
A = F
P

Question 16

What is mass?

Answer 16

The quantity of matter in object.(Related to weight, but not the same as weight.)

Measured by

a) how much gravity it exerts on other objects
b) how much it resists acceleration

Question 17

What is acceleration?

Answer 17

Change of speed and/or direction. (Strictly speaking, velocity implies both speed and direction.)

Question 18

What is Inertia?

Answer 18

tendency of object to remain in its current state, whether moving or still.

Question 19

Force overcomes inertia and results in

Answer 19

acceleration.

More force results in more acceleration.
More mass resists acceleration.

Question 20

We can measure Area and pressure but not force. How is force reflected?

Answer 20

Pressure measurement is an indication, a reflection,of force.