1. What is the full form of ECG?
a) Electricity cardiac group
b) Electrocardio group
c) Electrocardium granules
d) Electrocardiogram
View Answer
Answer: d
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?
a) One
b) Two
c) Three
d) Four
View Answer
Answer: c
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
d) T-wave
View Answer
Answer: a
Explanation: The correct representation of a standard ECG is given as follows:
4. Which of the following waves represent the excitation of the atria?
a) P-wave
b) QRS complex
c) T-wave
d) ST-segment
View Answer
Answer: a
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?
a) P-wave
b) T-wave
c) QRS complex
d) PQ interval
View Answer
Answer: c
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.
a) True
b) False
View Answer
Answer: a
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?
a) P-wave
b) QRS complex
c) ST-segment
d) PQ interval
View Answer
Answer: b
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
View Answer
Answer: a
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?
a) Ischemia
b) Hypokalemia
c) Myocardial infarction
d) Acute heart attack
View Answer
Answer: a
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
View Answer
Answer: c
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.