Inadequate supply of oxygen to heart muscles leads to a symptom of acute chest pain. This disorder of the circulatory system is identified as:
1. Angina pectoris
2. Cardiac arrest
3. Heart failure
4. Coronary Heart Disease
| List I | List II |
| A. P-wave | I. Ventricular repolarization-relaxation phase |
| B. P-R interval | II. The onset of ventricular depolarization - leads to ventricular contraction |
| C. QRS complex | III. Time for the impulse to be conducted from SA node to the ventricles through the AV node |
| D. T-wave | IV. Atrial depolarization - leads to atrial contraction |
| List I | List II |
| A. Bicuspid (mitral) valve | I. Between right atrium and right ventricle |
| B. Aortic semilunar valve | II. Between left atrium and left ventricle |
| C. Tricuspid valve | III. Between right ventricle and pulmonary artery |
| D. Pulmonary semilunar valve | IV. Between left ventricle and aorta |