1. What is the full form of ECG?
a) Electricity cardiac group
b) Electrocardio group
c) Electrocardium granules
Explanation: ECG stands for Electrocardiogram. ECG is a graphical representation of the electrical activity of the heart during a cardiac cycle. It is measured with the help of a machine called an electrocardiograph.
2. To measure ECG, usually how many electrodes are connected to a patient?
Explanation: To measure a standard ECG, a patient is connected to the machine with three electrical leads-one to each wrist and one to the left ankle. It continuously monitors heart activity.
3. Which of the following letters is marked incorrectly in the given diagram?
Find the letters marked incorrectly in the given ECG diagram
a) P & R
b) Q & T
c) T & S
Explanation: The correct representation of a standard ECG is given as follows:
4. Which of the following waves represent the excitation of the atria?
b) QRS complex
Explanation: The P-wave represents the electrical excitation of depolarisation of the atria which leads to the contraction of both the atria. The T-wave represents the repolarisation of the ventricles.
5. Which of the following represents the depolarisation of the ventricles?
c) QRS complex
d) PQ interval
Explanation: The QRS complex represents the depolarisation of the ventricles, which initiate the ventricular contraction. The contraction starts shortly after Q and marks the beginning of the systole.
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6. The end of the T-wave marks the end of the systole.
Explanation: The end of the T-wave marks the end of the systole. The T-wave represents the return of the ventricles from excited to normal state which is also known as repolarisation of the ventricles.
7. By counting the number of which of the following waves, the heartbeat of a person can be determined?
b) QRS complex
d) PQ interval
Explanation: By counting the number of QRS complexes that occur in a given period, one can determine the heartbeat rate of an individual. Any deviation from the shapes of the curve indicates a possible abnormality or a disease. Hence, it is of great clinical significance.
8. Which of the following represents the enlargement of auricles?
a) Enlargement of P-wave
b) Enlargement of QR segment
c) Depression of ST segment
d) Elevation of ST segment
Explanation: Enlargement of auricles is represented by the enlargement of P-wave or sometimes the lengthening of PQ interval also represents the enlargement of auricles by rheumatic fever.
9. What does the depression of ST-segment depict?
c) Myocardial infarction
d) Acute heart attack
Explanation: The depression of ST-segment shows Ischemia which means there is an insufficient supply of blood to the heart muscles or the weakening of the heart muscles.
10. Which of the following muscles have the longest refractive period?
a) Skeletal muscles
b) Smooth muscles
c) Cardiac muscles
d) Facial muscles
Explanation: Cardiac muscles never show the property of summation or tetanus spasm as the muscles have the longest refractory period. Cardiac muscles also have the least latent period.