Scientists believe that the heart of the common (chordate)ancestor of all vertebrates
A)was little more than a heavily-muscled region of the ventral artery.
B)had two chambers.
C)had three chambers.
D)had four chambers.
E)consisted of a single ventricle.

Question

Quizplus · Accepted Answer

The heart of the common ancestor of all vertebrates is believed to have been a simple structure, essentially a heavily-muscled region of the ventral artery, rather than a complex multi-chambered organ. This reflects an early stage in the evolution of the circulatory system.

Scientists Believe That the Heart of the Common (Chordate)ancestor of All