Can anyone help me understand the answer?
Warm-blooded animals have elaborate physiological
controls to maintain constant body temperature (in
humans, 37· C). Why then during sickness should
temperature rise, apparently increasing stress on the
infected organism? It has long been known that the level
of serum iron in animals falls during infection. Garibaldi
first suggested a relationship between fever and iron. He
found that microbial synthesis of siderophores -- substances
that bind iron in bacteria of the genus
Salmonella declined at environmental temperatures
above 37· C and stopped at 40.3· C. Thus, fever would
make it more difficult for an infecting bacterium to
acquire iron and thus to multiply. Cold-blooded animals
were used to test this hypothesis because their body
temperature can be controlled in the laboratory. Kluger
reported that of iguanas infected with the potentially
lethal bacterium A. hydrophilia. more survived at
temperatures of 42· C than at 37· C, even though
healthy animals prefer the lower temperature. When
animals at 42· C were injected with an iron solution,
however, mortality rates increased significantly.
Research to determine whether similar phenomena occur
in warm-blooded animals is sorely needed .
27. If it were to be determined that "similar phenomena
occur in warm-blooded animals" (lines 21-22), which
of the following, assuming each is possible, is likely
to be the most effective treatment for warm-blooded
animals with bacterial infections?
(A) Administering a medication that lowers the
animals' body temperature
(B) Injecting the animals with an iron solution
© Administering a medication that makes serum
iron unavailable to bacteria
(D) Providing the animals with reduced-iron diets .
(E) Keeping the animals in an environment with
temperatures higher than 37· C