Question

7. External and internal respiration.
Differences

Answer 1

Answer:

External respiration occurs in the lungs where oxygen diffuses into the blood and carbon dioxide diffuses into the alveolar air.

Internal respiration occurs in the metabolizing tissues, where oxygen diffuses out of the blood and carbon dioxide diffuses out of the cells.

Answer 2

Answer:

During the gas exchange in animals, oxygen and carbon dioxide diffuse in and out of the blood in lungs and metabolizing tissues. Oxygen is used in the cellular respiration, produces metabolic energy in order to carry out cellular functions. During cellular respiration, carbon dioxide is produced as a waste. The gas exchange occurs at the respiratory membrane in lungs and in metabolizing tissues like skeletal muscles. The partial pressure gradient of each gas determines the direction and the rate of diffusion across the respiratory membrane. The main difference between internal respiration and external respiration is that internal respiration refers to the gas exchange across the respiratory membrane in the metabolizing tissues whereas external respiration refers to the gas exchange across the respiratory membrane of lungs.