PLEASE HELP...THIS IS DRIVING ME NUTS!!!!!!! LOL
1.) In cardiac muscle,
A- calcium ions are not released from the sarcoplasmic reticulum.
B- calcium ions do not bind to troponin molecules.
C- calcium ions play no role in the process of contraction.
D- some of the calcium ion required for contraction comes from outside the cell
E- calcium ion plays an important role in repolarizing the membrane after the depolarization phase.
2.) Each of the following changes will result in increased blood flow to a tissue EXCEPT one. Identify the exception.
A- increased blood volume
B- decreased vessel diameter
C- increased blood pressure
D- decreased peripheral resistance
E- relaxation of precapillary sphincters
3.) Which of these will increase the heart rate?
A- sympathetic stimulation to the SA node
B- the application of epinephrine to the SA node
C- the application of acetylcholine to the SA node
D- a and b
E- a,b,and c
4.) Abnormally slow conduction through the ventricles would change the _________ in an ECG tracing.
A- P wave
B- T wave
C- QRS complex
D- P-R interval
E- R-T interval
5.) If the connection between the AV node and bundle of HISS becomes blocked,
A- the ventricles will beat faster
B- the ventricles will beat more slowly
C- the ventricular rate of contraction will not be affected
D-the stroke volume will increase
E- tachycardia will occur
6.) If a myocardial infarction results in the formation of scar tissue along the pathway of the left bundle branch,
A- cardiac arrhythmias may occur
B- blood flow to the lungs will decrease
C- the ventricle will contract more forcefully
D- conduction through the left ventricle would remain normal
E- the right ventricle will fail to contract
7.) If there is a blockage between the AV node and the AV bundle, how will this affect the appearance of the electrocardiogram?
A- the P-R interval will be smaller
B- the QRS interval will be longer
C- there will be more P waves than QRS complexes
D- there will be more QRS complexes than P waves
E- the T wave will disappear