Q19

[jackie8848]

I understand (A) is the correct answer, but why is (E) incorrect? The author mentions that " ...could be released in quantities favorable to...". Doesn't this imply the number of the altered bacteria was sufficient?

[timmydoeslsat]

I understand (A) is the correct answer, but why is (E) incorrect? The author mentions that " ...could be released in quantities favorable to...". Doesn't this imply the number of the altered bacteria was sufficient?

Answer choice E states: The altered bacteria were released into the environment in numbers sufficient to guarantee the validity of the experimental results.

We do not know what number is sufficient to guarantee the validity of the experimental results. Nor, do we know that such a number even exists.

We know they released enough quantity of this altered bacteria that could crowd out the non-altered type that causes frost damage. But we do not know that it is true that it is sufficient to guarantee the validity of the experimental results.

We were not given told what would guarantee the validity of such results.

[LSAT-Chang]

Hey Timmy,
is (C) wrong because of the word "MUCH" safer?? Lines 42-43 say that it is "safer" but is it because the answer choice is too strong and also because there is no metioning of "much effective"? I just don't understand when we could infer these things, and when we can't. Like some of the answer choices to some problems are correct because it is "inferrable". Is MUCH safer not something we can infer from safer?

[ivankrasnov88]

Hey Timmy,
is (C) wrong because of the word "MUCH" safer?? Lines 42-43 say that it is "safer" but is it because the answer choice is too strong and also because there is no metioning of "much effective"? I just don't understand when we could infer these things, and when we can't. Like some of the answer choices to some problems are correct because it is "inferrable". Is MUCH safer not something we can infer from safer?

I'm not speaking on behalf of Timmy (whose explanations are excellent by the way), but if I may chime in:

The reason why C is wrong isn't only because of the words 'much safer' or 'more effective', it's because no such comparison was made to Pseudomonas FLUORESCENS - in fact the proponents are only discussing the merits of Pseudomonas SYRINGAE.

We don't know the efficacy of PF vs PS relative to each other, just that P Syringae is safer than the ORIGINAL organism that it's derived from (which may or may not be PF).

[maryadkins]

Good discussion here! And as for why (A) is correct, see lines 40-41 ("altered only by the removal of the gene ...").

[magnusgan]

Removal of an offending gene does not necessarily mean that an organism will have one less gene. I majored in biomedical engineering and unless I'm so out of touch with current genetics (or Feb 1993 genetics...) genes which are removed must be replaced by another strand of genetic code (typically containing the selection marker).

Therefore there would still be the same number of genes. It would be missing the gene for frost resistance (because it has been replaced), but there would not be one less gene.

How can the right answer choice equate the two?

[ManhattanPrepLSAT1]

You're probably right about the process of genetics, but it doesn't matter! The passage states in lines 39-44 that the bacteria are different only in the fact that they lack the gene for frost damage. If that's the only difference, they do possess one less gene. Whatever strand they must have put back in, must have been a duplicate of another gene the bacteria already had or placebo of some sort.

But the bacteria clearly lack the gene for frost damage - so one less gene.

Hope that helps!

[phoebster21]

I understand why A is right, but I'm not quite sure why D isn't. The purpose of altering this phyto(whatver ) was so that the gene that caused frost bite would be removed from the plan so that the plant would stand a better chance against frost bite.

Is it wrong because of the word "several?"
The passage states "experiments suggest that deliberately releasing altered nonpathogenic PS could crowd out the non altered variety that causes frost damage"

Hence, wouldn't the genetically altered bacteria be antagonistic to the phytopathogens in the soil?

OR is it that the answer choice is too specific in saying that the frost bite happens in the "roots" of the crops, while the passage never explains exactly how they get frosbite...?

[yolandadadad]

also as a biological major student, i got this question wrong
'the gene responsible for the strain's propensity to ...' is not necessarily to be 'one gene'
since LSAT always emphasis on distinction of details, i thought this is a trap
so i picked (E)

[LaCrosse]

I understand why A is right, but I'm not quite sure why D isn't. The purpose of altering this phyto(whatver ) was so that the gene that caused frost bite would be removed from the plan so that the plant would stand a better chance against frost bite.

Is it wrong because of the word "several?"
The passage states "experiments suggest that deliberately releasing altered nonpathogenic PS could crowd out the non altered variety that causes frost damage"

Hence, wouldn't the genetically altered bacteria be antagonistic to the phytopathogens in the soil?

OR is it that the answer choice is too specific in saying that the frost bite happens in the "roots" of the crops, while the passage never explains exactly how they get frosbite...?

It seems the easiest way to disqualify (D) as the correct answer choice is to remember that the question asks us what the proponents of the use of genetically altered bacteria say about the altered bacteria used in the frost-damage experiments.

(D) might be factually true, but the proponents do not state that, the author of the passage does! The only thing that the proponents argue in relation to the frost-damage experiments (Paragraph 2) is what the answer choice (A) says.

[michellemyxu]

Why is B wrong? I chose B based on line 46-49.

[ohthatpatrick]

I'm confused by your supporting text.

What does line 46-49 (first sentence of the last paragraph) have to do with comparing
how altered bacteria did in the lab vs. how altered bacteria did in natural environments?

I'm assuming you were thinking of lines 54-56 (maybe your line numbers are different from mine).

This sentence says that altered bacteria may not compete as well in natural environments. It is speculatively looking to the future.

(B) makes it sound like we already tried them out in natural environments, the results are in, and they were not as viable.

Hope this helps.