Question

Сердечный цикл состоит из сокращений

Answer 1

Предсердий
желудочков
общего расслабление предсердий и желудочков

Answer 2

The Cardiac Cycle: Overview and Contraction

The cardiac cycle refers to the sequence of events that occur during one complete heartbeat. It consists of two main phases: diastole and systole. During diastole, the heart muscles relax and fill with blood, while during systole, the heart muscles contract and pump blood out of the heart.

During contraction (systole), the heart muscles contract to pump blood out of the heart and into the circulatory system. This phase can be further divided into two stages: atrial systole and ventricular systole.

- Atrial systole: The atria contract, pushing blood into the ventricles. This accounts for the first phase of ventricular filling. - Ventricular systole: The ventricles contract, pushing blood out of the heart. This phase can be further divided into two stages: isovolumetric contraction and ventricular ejection. - Isovolumetric contraction: The ventricles contract, but the valves leading to the major blood vessels (aorta and pulmonary artery) are still closed. This results in an increase in ventricular pressure without any change in volume. - Ventricular ejection: The ventricles continue to contract, causing the pressure to exceed the pressure in the major blood vessels. This opens the valves, allowing blood to be ejected into the aorta and pulmonary artery.

Relaxation and Filling: Diastole

During diastole, the heart muscles relax and fill with blood. This phase can also be divided into two stages: early diastole and late diastole.

- Early diastole: After ventricular ejection, the ventricles relax, and the pressure in the ventricles decreases. This causes the semilunar valves to close, preventing blood from flowing back into the ventricles. - Late diastole: The atria continue to fill with blood, and the ventricles are in a relaxed state. This allows the atrioventricular (AV) valves to open, allowing blood to flow from the atria into the ventricles.

Key Points:

- The cardiac cycle consists of two main phases: diastole and systole. - During systole, the heart muscles contract to pump blood out of the heart. - Systole can be further divided into atrial systole and ventricular systole. - During diastole, the heart muscles relax and fill with blood. - Diastole can be further divided into early diastole and late diastole. - The atrioventricular (AV) valves open during late diastole, allowing blood to flow from the atria into the ventricles.