Understanding Heart Cell Polarization and ECG Interpretation

What is the primary role of the electrical conduction system in the heart?

• To maintain a constant heart rate

• To send electrical signals for contraction and relaxation

• To regulate body temperature

• To increase blood pressure

What happens to a heart cell when it receives a jolt of electricity?

• It changes from negative to less negative

• It stops functioning

• It releases potassium ions

• It becomes impermeable to sodium

Which process in heart cells leads to contraction?

• Ionization

• Depolarization

• Repolarization

• Polarization

What does the P wave in the PQRST complex represent?

• Atrial repolarization

• Ventricular repolarization

• Atrial depolarization

• Ventricular depolarization

During which part of the PQRST complex does ventricular repolarization begin?

• ST segment

• T wave

• QRS complex

• P wave