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Lobsters usually develop one smaller, cutter claw and one

Expert replies
by aditya8062 » Fri Mar 01, 2013 11:39 pm
Lobsters usually develop one smaller, cutter claw and one larger, crucehr claw. To show that exercise determines which claw becomes the crusher, researchers placed young lobsters in tanks and repeatedly prompted them to grab a probe with one claw -- in each case always the same, randomly selected claw. In most, of the lobsters the grabbing claw became the crusher. But in a second, similar experiment, when lobsters were prompted to use both claws equally for grabbing, most matured with two cutter claws, even though each claw was exercised as much as the grabbing claws had been in the first experiment.

Which of the following is best supported by the information above?

a. Young lobsters usually exercise one claw more than the other.
b. Most lobsters raised in captivity will not develop a crusher claw.
c. Excerice is not a determining factor in the development of crusher claws in lobsters.
d. Cutter claws are more effective for grabbing than are crusher claws.
e. Young lobsters that do do not exercise either claw will nevertheless usually develop one crusher and one cutter claw.

my 1st question :
the OA is A but somehow i find it confusing :even if i agree that A is supported by 1st experiment then isn't 2nd experiment refuting it ? have a look at this line from 2nd experiment :even though each claw was exercised as much as the grabbing claws had been in the first experiment.
my 2nd question :how C is not the answer
my logic is : if i go by 1st experiment then the motto of 1st experiment was To show that exercise determines which claw becomes the crusher and eventually we landed up with the fact that lobster randomly picked one and made it a crusher claw so cant i conclude that exercise has no role what so ever in determining the crusher claw
instructors plz help
thanks and regards
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Source: — Critical Reasoning |

by dixitnagpal » Sat Mar 02, 2013 2:27 pm
aditya8062 wrote:Lobsters usually develop one smaller, cutter claw and one larger, crucehr claw. To show that exercise determines which claw becomes the crusher, researchers placed young lobsters in tanks and repeatedly prompted them to grab a probe with one claw -- in each case always the same, randomly selected claw. In most, of the lobsters the grabbing claw became the crusher. But in a second, similar experiment, when lobsters were prompted to use both claws equally for grabbing, most matured with two cutter claws, even though each claw was exercised as much as the grabbing claws had been in the first experiment.

Which of the following is best supported by the information above?

a. Young lobsters usually exercise one claw more than the other.
b. Most lobsters raised in captivity will not develop a crusher claw.
c. Excerice is not a determining factor in the development of crusher claws in lobsters.
d. Cutter claws are more effective for grabbing than are crusher claws.
e. Young lobsters that do do not exercise either claw will nevertheless usually develop one crusher and one cutter claw.

my 1st question :
the OA is A but somehow i find it confusing :even if i agree that A is supported by 1st experiment then isn't 2nd experiment refuting it ? have a look at this line from 2nd experiment :even though each claw was exercised as much as the grabbing claws had been in the first experiment.
my 2nd question :how C is not the answer
my logic is : if i go by 1st experiment then the motto of 1st experiment was To show that exercise determines which claw becomes the crusher and eventually we landed up with the fact that lobster randomly picked one and made it a crusher claw so cant i conclude that exercise has no role what so ever in determining the crusher claw
instructors plz help
thanks and regards
IMO:A is correct one.
Since the line u mentioned is just comparing that(as per experiment)even though the exercise is done same number of times by both claws and single claw.Yet usage of claw made deciding factor for the development fo claw into crusher. so its correct as experiment proved this.
So we cannot deny this experiment. I hope it clears your first doubt.
2nd Question: You are xactly gong in wrong direction as exercise is the determining factor for development of crusher.As argument itself is clearing it that exercising with both claws developed both into crushers and while only one developed to crusher when exercised with one claw.
I hope it clears your doubt.
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