Question

Which statement comparing the circulatory systems in mammals and birds is true?

a. Birds have far smaller hearts per gram.
b. Mammals have, on average, higher systolic blood pressures.
c. Mammals have a higher pressure systemic circuit.
d. Birds and mammals have essentially identical circulatory systems.

Answer 1

Birds and mammals have essentially identical circulatory systems, with a four-chambered heart and double circulation.

Step-by-step explanation:

The correct statement comparing the circulatory systems in mammals and birds is option d. Birds and mammals have essentially identical circulatory systems.

Mammals and birds both have a four-chambered heart and double circulation, which means that oxygenated and deoxygenated blood are completely separated. This allows for efficient oxygen delivery to the body and lungs. While there may be variations in heart size and blood pressures, the overall circulatory systems of mammals and birds are very similar.