問題詳情
27. Countercurrent exchange in the gills of a fish
(A) maintains a gradient that enhances diffusion.
(B) speeds up the flow of water through the gills.
(C) interferes with the efficient absorption of oxygen.
(D) means that blood and water flow in the same direction.
(E) enables the fish to obtain oxygen while swimming backward.
(A) maintains a gradient that enhances diffusion.
(B) speeds up the flow of water through the gills.
(C) interferes with the efficient absorption of oxygen.
(D) means that blood and water flow in the same direction.
(E) enables the fish to obtain oxygen while swimming backward.
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