試題詳解

54. Which of the following contributes to the high efficiency of gas exchange in fish gills?
(A) The high degree of oxygen saturation of water significantly contribute to high efficiency in gas exchange.
(B) The back-and-forth movement of water maximizes oxygen uptake.
(C) Very high blood pressure in the circulatory system of fishes contributes to high efficiency in gas exchange.
(D) The co-current exchange mechanism contributes highly to the gas exchange.
(E) The countercurrent exchange mechanism contributes highly to the gas exchange.