Match List I with List II:List I List II A. P Wave I. Heart muscles are electrically silent B. QRS complex II. Depolarisation of ventricles C. T wave III. Depolarisation of atria D. T-P gap IV. Repolarisation of ventricles
Choose the correct answer from the options given below:
| List I | List II |
|---|---|
| A. P Wave | I. Heart muscles are electrically silent |
| B. QRS complex | II. Depolarisation of ventricles |
| C. T wave | III. Depolarisation of atria |
| D. T-P gap | IV. Repolarisation of ventricles |
Answer: (A) A-III, B-II, C-IV, D-I. Answer: (a) A-III, B-II, C-IV, D-I Solution: The P-wave is depolarisation of the atria (III); the QRS complex is depolarisation of the ventricles (II); the T-wave is repolarisation of the ventricles (IV); and during the T-P gap the heart muscles are electrically silent, i.e.
- A.A-III, B-II, C-IV, D-I✓
- B.A-II, B-III, C-I, D-IV
- C.A-IV, B-II, C-I, D-III
- D.A-I, B-III, C-IV, D-II
Correct Answer
(A) A-III, B-II, C-IV, D-I
Solution & Explanation
Answer: (a) A-III, B-II, C-IV, D-I Solution: The P-wave is depolarisation of the atria (III); the QRS complex is depolarisation of the ventricles (II); the T-wave is repolarisation of the ventricles (IV); and during the T-P gap the heart muscles are electrically silent, i.e. the resting interval between cycles (I). This matches A-III, B-II, C-IV, D-I. NCERT: Ch 15, p.201, line 13 — "The P-wave represents the electrical excitation (or depolarisation) of the atria"