Which of the following statements comparing respiration in fish and in mammals is correct?
A) The respiratory medium for fish carries more oxygen than the respiratory medium of mammals.
B) A countercurrent exchange mechanism between the respiratory medium and blood flow is seen in mammals but not in fish.
C) The movement of the respiratory medium in mammals is bidirectional, but in fish it is unidirectional.
D) In blood, oxygen is primarily transported by plasma in fish, but by red blood cells in mammals.

Question

Quizplus · Accepted Answer

In fish, respiration occurs through gills, where water flows in a unidirectional manner over the gill filaments. In mammals, respiration occurs in the lungs, where the movement of air is bidirectional. Therefore, option C is the correct comparison between respiration in fish and mammals. Option A is incorrect because fish extract oxygen from water, which carries less oxygen compared to air. Option B is incorrect because countercurrent exchange mechanism is seen in both fish and mammals. Option D is incorrect because oxygen is mainly transported by red blood cells in both fish and mammals.

Which of the Following Statements Comparing Respiration in Fish and in Mammals