Exam 22: A: Physiology of the Cardiovascular System

Blood vessels can hold much more blood than is present in the body.

If resistance in the blood vessels remains constant,then the minute volume of blood is directly related to the difference between arterial and venous pressure.

During a normal ECG,the tracing should never go below the zero mark of the graph.

The pressure gradient in the ventricles exceeds the pressure in the pulmonary artery and aorta.

Osmotic pressure tends to move plasma out of the capillary and into the tissues.

The contraction of the heart is referred to as systole.

In both the atria and ventricles,the first cells to depolarize are also the first cells to repolarize.

Based on the Starling law of the heart,the greater the venous return,the stronger the heart contraction.

Blood viscosity is caused by both red blood cells and the protein concentration of the blood.

As the elasticity of the artery wall decreases,the magnitude of the pulse wave increases.

In an ECG,both the deflections themselves and the interval between deflections can provide information about the electrical conduction through the heart.

The volume of blood circulated per minute is equal to the difference between the mean arterial pressure and the central venous pressure,divided by the resistance.

Tachycardia is normal during sleep and in conditioned athletes while they are awake (but at rest).

If a pulse were taken at the popliteal and dorsalis pedis arteries at the same time,it would be felt at the popliteal artery first.

Under resting conditions,the SA node fires at an intrinsic rhythmical rate of 80 to 85 beats per minute.

The subendocardial fibers and Purkinje fibers refer to the same structures.

The last wave in an ECG terminates the cardiac cycle; because of this,it is called the T wave.

The contraction phase of the cardiac cycle refers to diastole.

Residual volume refers to the blood that remains in the ventricle after the ejection period.

The pulse wave is associated with left ventricular diastole.