The Living World 8th Edition by George Johnson

Exercise 12

Additional septa in the amphibian and reptile heart allow for
A) higher blood pressure to move blood faster.
B) better separation of oxygenated and deoxygenated blood.
C) better body temperature regulation.
D) better transport of food to needy tissues.
The difference between the amphibian and mammal hearts is that
A) in the amphibian heart, oxygenated and deoxygenated blood mix completely in the single ventricle.
B) in the amphibian heart, there are two SA nodes so that contractions occur simultaneously throughout the heart.
C) in the ventricle in the amphibian heart, internal channels reduce mixing of blood.
D) in the amphibian heart, only the left aorta pumps oxygen obtained by diffusion through the skin.