The name of the pace maker of the heart is
lymph node
SA node
juxtaglomerular apparatus
semilunar valve
B.
SA node
The heart beat originates from sinoatrial node (SA node) also called pacemaker, which lies in the wall of right atrium near the opening of superior vena cava. This can be remedied by surgical grafting of artificial pacemaker in chest of patient.
What would be the heart rate of a person if the cardiac output is 5 L, blood volume in the ventricles at the end of diastole is 100 mL and at the end of ventricular systole is 50 mL?
75 beats per minute
100 beats per minute
125 beats per minute
50 beats per minute
Muscles of the heart are
striated and voluntary
non-striated and voluntary
striated, unbranched and involuntary
non-striated and involuntary
non-striated and involuntary
Match the Column-I with Column-II
| Column I | Column II |
| A. P-wave | (i) Depolarisation of ventricles |
| B. QRS complex | (ii) Repolarisation of ventricles |
| C. T-wave | (iii) Coronary ischemia |
| D. Reduction in the size of T-wave |
(iv) Depolarisation of atria (v) Repolarisation of atria |
Select the correct option.
A - (iv); B - (i); C - (ii); D - (v)
A - (ii); B - (i); C - (v); D - (iii)
A - (ii); B - (iii); C - (v); D - (iv)
A - (iv); B - (i); C - (ii); D - (iii)
The granulocytes which secretes histamine, serotonin and heparin are
Neutrophilss
Basophils
Eosinophils
Lymphocytes
Lymphocytes
In a cardiac cycle, if the stoke volume is 70 ml and heart rate is 72 beats/minute, then cardiac output is
142 ml/minute
72 ml/minute
1070 ml/minute
70 ml/minute
70 ml/minute
Choose the wrong statement regarding human blood and circulatory system
Persons with blood group AB can receive blood from any person with any blood group
Calcium ions play an important role in blood clotting
Angina is acute chest pain when enough oxygen does not reach the brain
In a myogenic heart the normal activities are regulated intrinsically
In a myogenic heart the normal activities are regulated intrinsically
