Zaymiey

🔬 Biology  ·  Body Fluids and Circulation  ·  NEET

During the cardiac cycle, the period when both atria and ventricles are relaxed is called:

Answer: Joint diastole, when both chambers rest together.

  • A Joint diastole, when both chambers rest together
  • B Isovolumetric contraction, a brief tension phase
  • C Atrial systole, when atria are contracting
  • D Ventricular systole, when ventricles are contracting

Correct answer: A. Joint diastole, when both chambers rest together

Explanation: During joint diastole, both the atria and ventricles are relaxed simultaneously, allowing blood to passively fill the atria before the next cycle begins.

ECG: The Three Key WavesP wave(atrial depol.)QRS complex(ventricular depol.)T wave(ventricular repol.)QRS is the tallest spike - ventricles have far more muscle mass than the atria

A single ECG cycle: the P wave marks atrial depolarisation (contraction signal), the large QRS complex marks ventricular depolarisation, and the T wave marks ventricular repolarisation (recovery) before the next cycle begins.

Concept context

Blood, lymph, the heart, the cardiac cycle, blood pressure, and ECG. High NEET weightage.

Read the full Body Fluids and Circulation notes →