Either the cardiac system or muscular system, depending on what you are covering.
The human heart.
heart
heart
A human feature is a body part. For example a heart.
Ventricles are present in the heart of the human body.
Human body big part first is Heart .. second is Eye .... I'm OK or not I don't know
the heart
the brain is the oldest part of the body there is also the skin cells it is also the heart
heart
Yes the hearth is the main part of the human body so yes
The human heart works with EVERY organ system in the body. Everything in the human body needs blood to survive and the heart provides that blood be pumped to every part of the body.
every part of the body senses change, but if the question means which part senses first, the answer is the heart.