All vertebrate cardiovascular systems include a heart, a muscular pump that contracts to (i) ________ .blood through the blood vessels. The upper chamber of the heart is the atrium, and is where blood enters the muscle. The lower chamber is the ventricle. When the ventricle (ii) ________ , blood is forced from the heart via an artery. The aorta is the main artery leaving the heart and bringing nutrients and oxygen out to the other organs. The pulmonary artery returns the oxygen-(iii) ________ .blood to the heart so that it can be enriched with nutrients and sent back out into the body.

Blank (i)	Blank (ii)	Blank (iii)
A. pitch	D. constricts	G. squandered
B. propel	E. compresses	H. augmented
C. project	F. cinches	I. depleted