NEET 2013 · Class 11

Body Fluids and Circulation

[DIAGRAM: A standard electrocardiogram (ECG) trace of a normal person showing the P wave, QRS complex, and T wave.] The diagram given here is the standard ECG of a normal person. The P-wave represents the

  1. (A)beginning of the systole
  2. (B)end of systole
  3. (C)contraction of both the atria
  4. (D)initiation of the ventricular contraction

The NCERT line that answers it

Verbatim line

The P-wave represents the electrical excitation (or depolarisation) of the atria, which leads to the contraction of both the atria.

Chapter
Body Fluids and Circulation
Section
15.3.3 Electrocardiogram (ECG)
Page
8
Words matched
20 of 20

The answer appears as a continuous sentence in NCERT. This is that sentence.

How this line gives the answer

0, emb=1.0, combined=1.0). Verified: high — The span explicitly states 'The P-wave represents the electrical excitation (or depolarisation) of the atria, which leads to the contraction of both the atria', which directly matches option C and distinguishes it from other options.

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