CVS GBL 25

In a healthy adult, which of the following is the primary determinant of blood flow distribution in different organs and tissues?

• Cardiac output

• Arterial pressure

• Vascular resistance

• Venous return

When blood pressure increases, the myogenic mechanism in small arteries and arterioles causes the vessel to:

• dilate and allow more blood flow.

• constrict and prevent excessive blood flow.

• unchanged to maintain constant blood flow.

• be more permeable to allow fluid exchange.

Which of the following increases preload in the heart?

• Prolonged standing

• Pregnancy

• Expiration

• Vomiting

Which of the following factors decreases cardiac output?

• Decrease in vagal tone

• Accumulation of potassium in the extracellular fluid

• Increased in calcium in the cytosol

• Decrease in afterload

What is the duration time of a complete cardiac cycle?

 

• 0.2s

• 0.4s

• 0.6s

• 0.8s

 

At which phase of cardiac cycle the second heart sound can be heard?

• 2nd phase

• 3rd phase

• 4th phase

• 5th phase

Which mechanism is responsible for the redistribution of blood flow during exercise?

• Activation of the renin-angiotensin-aldosterone system
  

• Selective vasodilation in skeletal muscles
  

• Increased vagal tone to the heart
  

• Chemoreceptor activation in response to hyperoxia

The baroreceptor reflex primarily influences which physiological parameter to stabilize acute changes in blood pressure?

• Heart rate
  

• Blood viscosity
  

• Peripheral resistance
  

• Venous compliance

Which of the following best describes the PR interval in an ECG?

• The time taken for ventricular depolarization and repolarization
  

• The time between the onset of atrial depolarization and the onset of ventricular depolarization
  

• The period with no electrical activity between ventricular depolarization and repolarization
  

• The time taken for the atrial repolarization

If a wave of depolarization moves 90 degree to the lead axis, what is the expected deflection on the ECG?

• Positive deflection

• Negative deflection

• Zero potential

• A mix of positive and negative deflection