Unit 12-2 Physiology of Cardiovascular System Flashcards
If a pressure difference exists, a ___ will flow
Fluid
Pressure differences are determined by what 2 things?
- The pressure generated
2. Resistance to flow
What are the 4 characteristics of cardiac muscle?
- Automatic contraction
- Inherit rhythm
- All-or-none contraction
- Long refractory period
HR is ____ beats/minute
70
SV is ___ ml/beat(by each ventricle)
70
What is chronotrophy?
A change in HR
What is inotropy?
A change in force of contraction
Systole is ___ and diastole is ___; if an average cardia cycle rest lasts 0.8 of a second
Contraction; relaxation
Atrial systole occurs in the ___sec
0.1
Ventricular systole occurs in the __,___,__ sec
0.2;0.3;0.4
Atrial Diastole occurs in the ___ seconds
0.2-0.8
Ventricular diastole occurs in the ___ and ___ second
0.1; 0.5-0.8
The heart has 2 sounds ___ and __, the first sound occurs after the start of the ____, the second sound occurs after the end of the ___
Lub;dub; Ventricular systole
___ determines opening and closing of the valves
Pressure
____ pressure ranges between 0 and 20mmHg
Atrial
___pressure ranges from 0 to 120 mmHg
Left Ventricular
___pressure ranges from 80 to 120 mmHG
Aortic
Av valves are ___ when atrial pressure is greater than ventricular pressure, and ____ when atrial pressure is lower then ventricualr pressure
Open; closed
Semilunar valves are ___ when aortic pressure is greater than ventricular pressure, and ___ when aortic pressure is lower thatn ventricular pressure
Closed, open
Ventricular volume flow in due to ___, absent bc AV and semilunar valves are ___, flow out due to ____, flow absent bc AV and semilunar valves are ___, flow in during ____
Atrial systol; closed; Ventricular diastole; closed; ventricular diastole
Atrial pressure flow in due to difference between ___ and ___ pressure and flow out due to difference between ____ and ____ pressure
Venous; Atrial; Atrial; Ventricular
Ventricular pressure flow in due to ____, flow out due to ___, flow in due to difference between ___ and ___ pressure
Atrial systol; Ventricular systol; Atrial; ventricular
Aortic pressure flow ___from the heart, flow in due to ___, dictrotic notch due to ___ of elastic wall, flow ___ from the heart
Away; Ventricular systol; Recoil; Away
Intrinsic coordination of the cardia cycle involves a _____ system
Conducting
The conducting system conducts ____ impulses(depolarization)
Cardiac
The cardiac impulse stimulates cardiac muscle to ____
Contract
Teh velocity of conduction of the cardiac impulse is the ___ wehter the heart is beating fast or slow
Same
Length of ____ is always the same
systole
Length of ___ varies
diastole
The diameter of the conducting fibers determines the ___ of conduction, ___ fibers conduct fast, ___ fibers conduct slow
Velocity; Large; Small
The conducting system is displayed with the _____
Electrocardiogram
The ECG is a measure of ___ generated in _____ fluids of the body by depolarization of many cardiac muscles
Current, Extracellular
Cardiac muscle depolarization lasts about ___ seconds
0.30
What are the 4 components of the ECG?
- P wave
- QRS complex
- T wave
- Base
What are the 4 intervals and durations of the ECG?
- PR interval
- QRS duration
- RT interval
- TR interval
A normal sinus rhythm is a normal ECG arising from the ___-
SA node
Cardiac arrhythmias include the following 3 things?
- Origination of the cardiac impulse from an abnormal location
- Disorders of conduction
- Abnormal pacemaker rhythm
What is Cardiac output?
Blood pumped per minute by each ventricle
Teh average CO at rest is __ L/min
5
During the strenuous exercise in a well trained person, the CO may increase to ___L/min
25
The cardiac reserve is the difference between the rest and ______
Maximum CO
CO is determined by 2 factors?
- Heart rate
2. Stroke volume
In order to increase (decrease) CO, Increase (decrease) ___ will occur due to Decrease(increase) ____- input to the heart, Increase(decrease) ____ input to the heart, Increase(decrease) circulating ____, Increase(decrease) _____
HR; Parasympathetic; Sympathetic; Epinephrine; body temperature
In order to Increase (decrease) CO, Increase (decrease) SV will occur that is due to Increase(decrease) ___ input to the heart. Increase (decrease) ____
SNS; Ventricular stretch
What results from congestive heart failure?
- Left ventricle leads to pulmonary edema
2. Right ventricle failure leads to systemic edema
____ and ___ control blood flow
Pressure; resistance
BP is determined by what 2 things?
- Blood volume
2. Arteriolar resistance
Systolic pressure occurs during systol, due to ___ of the heart
Contraction
Diastolic pressure occurs during diastole; due to ____ of blood that remains in the arteries after peripheral runoff
Volume
The ___ pressure is the difference between systolic and diastolic pressure
Pulse
The mean arterial pressure is essentially the ___ throughout the arterial tree, resistance is also essentially the ___ throughout the arterial tree
Same
The function of resistance is to control _____ to different organs
blood flow
____ is increased blood flow
Hyperemia
_____ is decreased blood flow
Ischemia
Resistance is determined by what 3 things?
- Viscosity of blood
- Length of vessel
- Diameter (radius) of vessel
____ is the chief determinant of resistance
Arteriolar diameter
_____ is the resistance in the systemic circuit
Peripheral
____ is the resistance in the pulmonary circuit
Pulmonary
