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knewton cr hw 15

Expert replies
by pradeepkaushal9518 » Wed Oct 13, 2010 10:33 pm
Identify a strategy the scientists might use to resolve the problem below:

Luciferase is the name of the category of enzymes that allow living creatures, such as fireflies, to emit light. Scientists believe that oxygen is needed to activate luciferase, but they find this difficult to test because when they deprive fireflies of oxygen, the fireflies die and the luciferase does not light.

A
Scientists might try breeding fireflies in an oxygen-free environment.
B
Scientists might try to genetically engineer other animals so that they can emit light without using luciferase.
C
Scientists might buy vast numbers of extra fireflies to replace any who died during the experimentation.
D
Scientists might try to engineer luciferase into organisms that do not need oxygen to survive.
E
Scientists might try to isolate luciferase in an oxygen-rich environment to see if it glows without fireflies.

oa is D
Last edited by pradeepkaushal9518 on Fri Oct 15, 2010 10:33 pm, edited 1 time in total.
A SMALL TOWN GUY
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Source: — Critical Reasoning |

by shovan85 » Thu Oct 14, 2010 2:04 am
Need to experiment on luciferase. But not able to do so as firefly dies in an oxygen-free environment. So we need the organism to be alive in oxygen-deprived environment.

Clearly IMO D
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by nisha.menon294 » Thu Oct 14, 2010 3:59 am
i think it is E. oa please?
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by pesfunk » Thu Oct 14, 2010 7:38 am
IMO D
nisha.menon294 wrote:i think it is E. oa please?
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by psychomath » Thu Oct 14, 2010 7:57 am
I will go with D here....
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by diebeatsthegmat » Fri Oct 15, 2010 5:54 pm
pradeepkaushal9518 wrote:Identify a strategy the scientists might use to resolve the problem below:

Luciferase is the name of the category of enzymes that allow living creatures, such as fireflies, to emit light. Scientists believe that oxygen is needed to activate luciferase, but they find this difficult to test because when they deprive fireflies of oxygen, the fireflies die and the luciferase does not light.

A
Scientists might try breeding fireflies in an oxygen-free environment.
B
Scientists might try to genetically engineer other animals so that they can emit light without using luciferase.
C
Scientists might buy vast numbers of extra fireflies to replace any who died during the experimentation.
D
Scientists might try to engineer luciferase into organisms that do not need oxygen to survive.
E
Scientists might try to isolate luciferase in an oxygen-rich environment to see if it glows without fireflies.
both E and D make sense....hmhmhm
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by neerajkumar1_1 » Fri Oct 15, 2010 9:18 pm
Pick E...
the enzyme Luciferase is in question... whether it lights up or not in oxygen...
to keep the options pragmatic...

Scientists might try to isolate luciferase in an oxygen-rich environment to see if it glows without fireflies.

this will tell u whether oxygen is the activating factor
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by this_time_i_will » Sat Oct 16, 2010 11:09 pm
The premise clearly tells that scientists need an oxygen free environment to test their hypothesis.
so any option that taks about oxygen free environment and at the same time removes the problem(= that fireflies die in oxygen free environment) faces by the scientists, would do the trick.
Hence, IMO D.

The hypothesis that scientists want to test is whether oxygen is required or not. Not, whether fireflies are required or not.
so, IMO, we can discard E.
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by Dangerous Dude » Sun Oct 17, 2010 2:48 am
What i can say...


As per the argument it is not possible to test luciferous in oxygen deficient enviroment because organism dies.... so organism is necessary to test the luciferous.... and luciferous has to be tested in oxygen deficinet environment... Combining these two .. we can have only D as the possible solution...

I pick D
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