試題詳解

41. Blood flukes are parasitic flatworms that live in the bloodstream of the host. The worm’s interstitial fluids are isoosmotic to the host’s blood, so which of these is true?
(A)The worms lack flame bulbs.
(B)The worms have flame bulbs whose role is to eliminate excess water that enters the worm.
(C)The worms have flame bulbs whose role is to concentrate urine.
(D) The worms have flame bulbs that eliminate nitrogenous wastes.
(E)The worms have flame bulbs that absorb nutrients from the host.