Which of these statements accurately describes the heart? Check all that apply.

A) The heart is a double pump.
B) The heart helps maintain blood pressure.
C) The heart makes red blood cells.
D) The heart is composed primarily of muscle.
E) The heart has an inner lining made of endothelium.

A) The heart is a double pump, meaning it has two different circulatory systems (pulmonary and systemic) that it pumps blood to.
B) The heart helps maintain blood pressure by pumping blood throughout the body and therefore regulating the pressure in the arteries.
C) The heart does not make red blood cells, that is the job of the bone marrow.
D) The heart is primarily composed of muscle, specifically cardiac muscle.
E) The heart has an inner lining made of endothelium, which is a thin layer of cells that helps protect and lubricate the heart's chambers.