Ventricular contractions are larger because

Answer 1

The ventricles are the part of the heart that are responsible for the pumping action to move blood throughout the body. Therefore, the muscles in the ventricles are much larger and thicker to do their job properly. The atrium only has to pump blood through an open valve (the tricuspid valve) into the right ventricle. There is

much less resistance to this flow of blood so much less muscle is needed.

Answer 2

I will answer this assuming that the question is comparing ventricular contractions to atrial contractions.

The upper right part of the heart is where blood comes to the heart to be pumped. Deoxygenated blood enters the right atrium from the vena cava. Oxygenated blood from the lungs enters the left atrium from the pulmonary vein. The blood enters these atria while the atria are relaxed.

A signal from the heart's pacemaker causes the atria to contract pushing blood into the ventricles, the larger more muscular part of the heart. The atria have to push the right volume of blood hard enough to mildly stretch the relaxed ventricular muscle (healthy hearts know how much and how hard - they get lots of practice). By the time the pacemaker's signal reaches the ventricles, the atria have finished pushing.

Now the ventricles contract with a much greater power to make sure that the blood reaches all parts of the body. The right ventricle has a less powerful contraction than the left because it delivers blood only to the lungs. The left ventricle delivers blood everywhere else.

Answer 3

Ventricular contraction is seen as a larger wave on an electrocardiogram (ECG) because the 2 lower chambers of the heart (ventricles) are larger in size than the 2 upper chambers (atria) and therefore, require more electrical energy to make them contract.

Answer 4

Ventricular contractions produce a greater force than atrial contractions, so they are represented by a larger wave pattern on the oscilloscope. The waves are larger because they push blood through the entire body instead of the atrial contractions that only push blood to the heart.