Match List I with List II.
| List I |
List II |
||
| A. | P-wave | I. |
Beginning of systole |
| B. | Q -wave | II. |
Repolarisation of ventricles |
| C. | QRS complex | III. |
Depolarisation of atria |
| D. | T-wave | IV. |
Depolarisation of ventricles |
Choose the correct answer from the options given below:
A-III, B-I, C-IV, D-II
A-IV, B-III, C-II, D-I
A-II, B-IV, C-I, D-III
A-I, B-II, C-III, D-IV
A. P-wave: The P-wave represents the depolarization (contraction) of the atria. It corresponds to the beginning of systole, which is the contraction phase of the cardiac cycle. Therefore, the correct pairing is A-III.
B. Q-wave: The Q-wave is a small downward deflection that appears before the R-wave in the QRS complex. It doesn't have a specific physiological event associated with it. Therefore, the correct pairing is B-I.
C. QRS complex: The QRS complex represents the depolarization (contraction) of the ventricles. It is the largest and most prominent wave complex on the ECG. It occurs during the ventricular systole phase, which is the main pumping phase of the cardiac cycle. Therefore, the correct pairing is C-IV.
D. T-wave: The T-wave represents the repolarization (relaxation) of the ventricles. It occurs during the diastole phase, which is the relaxation phase of the cardiac cycle. Therefore, the correct pairing is D-II.
Based on the explanations above, we can conclude that Option 1) A-III, B-I, C-IV, D-II is the correct answer.