Answer:
is part of the cardiovascular system;
pumps blood to the cells in the body works;
closely with the lungs
Explanation:
The heart is a muscle that pumps blood through the blood vessels and that is the essential function. It is the main and central organ of the circulatory system.
The heart weights between 200 and 425 grams. It is located between lungs, in the middle of the chest and it is divided into four chambers in humans, other mammals, and birds heart.
