When is a pulse formed?

A pulse is formed primarily when the left ventricle contracts. This contraction, known as systole, pumps blood into the aorta and the systemic circulation. As blood is ejected forcefully from the heart into the arteries, it creates a pressure wave that travels through the arterial system. This is what we feel as a pulse in various locations of the body, such as the wrist or neck. The strength and rhythm of the pulse can provide important information about an individual’s cardiovascular health.

The other choices do not directly relate to the formation of a pulse. The contraction of the right atrium primarily facilitates the filling of the right ventricle rather than producing a significant pressure wave felt as a pulse. When the heart is at rest, during diastole, the left ventricle is filling with blood rather than actively pushing it out, which would mean no pulse is generated at that time. The filtering of blood through the kidneys, while essential for managing body fluids and electrolytes, does not relate to the mechanical action of the heart that creates a pulse.