Which of the following processes are unique to the respiratory system?
a. pulmonary ventilation and external respiration
b. external and internal respiration
c. pulmonary ventilation and internal respiration
d. pulmonary ventilation and transport of respiratory gases

pulmonary ventilation and external respiration

Explanation:

Respiration includes pulmonary ventilation, external respiration, and internal respiration. Pulmonary ventilation is also called breathing and is the process of flow of air into and out of the lungs. It includes the flow of air between the atmosphere and the alveoli of the lungs and is driven by alternating pressure differences created by contraction and relaxation of respiratory muscles.

External respiration is also called pulmonary respiration. It refers to the exchange of gases between the alveoli of the lungs and the blood in pulmonary capillaries. The exchange occurs through the respiratory membrane. External respiration males the capillary blood rich in O2. The capillary blood loses CO2 during the process.

explanation:

the fossil record extends back to a dog-like ancestor some 55 million years ago, which gave rise to the first horse-like species 55 to 42 million years ago in the genus eohippus.

some scientists like gregory adcock agree with thorne's theory of regional continuity.

others, like chris stringer and ian tattersall, believe thorne's results may be contaminated or misinterpreted.