What device on the ECG magnifies the heart's electrical impulses so they can be recorded?

• A. Augmented leads
• B. Amplifier
• C. Baseline
• D. Bundle branches

Answer: (B)

Heart electrical activity is recorded as very tiny millivolt signals, so the device used to visualize them is an amplifier. It boosts the strength of the signal without distorting its waveform, making the P waves, QRS complexes, and T waves clear on the tracing. The baseline is just the reference line on the recording, not a magnification device. Augmented leads are a way of configuring limb electrodes to measure potentials, not a signal boost. Bundle branches are part of the heart’s conduction system. So the amplifier is the component that magnifies the heart’s electrical impulses for recording.