CVS PHYSIO

A person’s electrocardiogram (ECG) has no P wave, but has a normal QRS complex and a normal T wave. Therefore, his pacemaker is located in the

• SA

• AV

• Bundle of HIS

• Purkinje system

• Ventricular muscle

If the ejection fraction increases, there will be a decrease in

• cardiac output

• end diastolic volume

• stroke vol

• pulse pressure

• Heart rate

In a healthy young male, left ventricular end-diastolic volume is estimated to be 150ml. His end- systolic volume is 80ml. His heart rate is 70 beats/minutes at rest. What is his estimated cardiac output?

• 3900ml/ min

• 4400

• 4900

• 5400

An athlete had ankle sprain during vigorous training and presents with swelling foot .X ray showed no fracture.  What is the cause of swelling in this case?

• Increased capillary permeability

• Increased capillary hydrostatic pressure

• Increased capillary oncotic pressure

• Venous obstruction

During the exercise if heart rate is doubled then cardiac cycle time will be

• 0.8 sec

• 0.4 sec

• 1.2 sec

• 0.2 sec

Regarding cardiac cycle

• S2 at start of T wave

• P wave is followed by T wave

• 1st heart sound is produced in isovolumetric ventricular contraction

• 1st heart sound is produced in isovolumetric ventricular relaxation

fastest control of blood pressure is achieved by

• CNS ischemic response

• chemoreceptors

• Barroreceptors

• RAAS

SA node acts as a pacemaker because of which of the following quality

• automaticity

• more gap junctions

• highest frequency of firing rate than others

• funny sodium channels

which of the following represent complete ventricular systole on ECG

• QRS complex

• PR Segment

• p wave

• ST segment

S2 heart sound produced by closure of the

• mitral valve

• tricuspid valve

• aortic and pulmonary valve

• none of the above