vomhorizon wrote:
A cup of raw milk, after being heated in a microwave oven to 50 degrees Celsius, contains half its initial concentration of a particular enzyme, lysozyme. If, however, the milk reaches that temperature through exposure to a conventional heat source of 50 degrees Celsius, it will contain nearly all of its initial concentration of the enzyme. Therefore, what destroys the enzyme is not heat but microwaves, which generate heat.
Which one of the following, if true, most seriously
weakens the argument?
(A) Heating raw milk in a microwave oven to a
temperature of 100 degrees Celsius destroys
nearly all of the lysozyme initially present in
that milk.
(B) Enzymes in raw milk that are destroyed through
excessive heating can be replaced by adding
enzymes that have been extracted from other
sources.
(C) A liquid exposed to a conventional heat source
of exactly 50 degrees Celsius will reach that
temperature more slowly than it would if it
were exposed to a conventional heat source
hotter than 50 degrees Celsius.
(D) Milk that has been heated in a microwave oven
does not taste noticeably different from milk
that has been briefly heated by exposure to a
conventional heat source.
(E) Heating any liquid by microwave creates small
zones within it that are much hotter than the
overall temperature that the liquid will
ultimately reach.
OA, after discussion
OA has to be E.(A) Heating raw milk in a microwave oven to a
temperature of 100 degrees Celsius destroys
nearly all of the lysozyme initially present in
that milk.
- WORNG because it still doesn't show that the heat, not the microwaves, is killing the bacterium. (B) Enzymes in raw milk that are destroyed through
excessive heating can be replaced by adding
enzymes that have been extracted from other
sources.
So? This is irrelevant to the argument.
(C) A liquid exposed to a conventional heat source
of exactly 50 degrees Celsius will reach that
temperature more slowly than it would if it
were exposed to a conventional heat source
hotter than 50 degrees Celsius.
this bring out wrong comparison. (D) Milk that has been heated in a microwave oven
does not taste noticeably different from milk
that has been briefly heated by exposure to a
conventional heat source.
taste is irrelevant to the argument. (E) Heating any liquid by microwave creates small
zones within it that are much hotter than the
overall temperature that the liquid will
ultimately reach.
PREFECT.
this weakens the link between the premise and conclusion.
Author's argument depends on the fact that even the conventional heat method reaches same 50 D but no germs are killed so microwaves generated in the Microwave is destroying germs. This option E shows that heat generated in the MW is more than 50 D making this comparisons invalid and the argument.
Im starting to like LSAT CRs
Kudos,if my posts helped.