Gist of the pasaage

The passage talks about the experiments conducted by scientist since 1953 to show how simplest organism are formed on the Earth.One hypothesis is that these organisms were present in oceans and atmosphere these when oxygen was abundant in the atmosphere synthesized slowly. .Some scientist said that earth had different gases like Ammonia Hydrogen and Methane dominate the atmosphere So it was covered by ocean and this ultimately undermines the theory that we living organism in the atmosphere.Although they couldn't present how these relatively small molecules combined to produce larger, more complex molecules.


24 As the passage mentions the presence of Hydrogen, ammonia and methane during the primitive years and that they contributed in the formation of complex molecules.
So A is the first option.


25 As mentioned in the Gist this about scients experiments since 1953 and thereois on how life began on earth. So option C


26 This question can be answered from scrutinizing the third line "They have demonstrated, however, that a variety of the complex molecules currently making up living organisms could have been present in the early ocean and atmosphere"

The words "currently making up" means that today's life on earth were synthesized from those complex compounds.So option C


27 As mentioned in the gist the scientist cound'nt not predict how synthesization had happened. "but none of these experiments have produced anything approaching the complexity of the simplest organism." these line suggest that.

Dismay is extreme and can be elminated.Anthipathy for the same reason can be eliminated as well.
He definitely didn't have a positive outlook on their developments so D. Scepticism

I think that the evidence to question 26 is wrong because it is mentioned that the scientists in line 20

Hi,

They have demonstrated, however, that a variety of the complex molecules currently making up living organisms could have been present in the early ocean and atmosphere, with only one limitation: such molecules are synthesized far less readily when oxygen-containing compounds dominate the atmosphere. Therefore some scientists postulate that the Earth's earliest atmosphere, unlike that of today, was dominated by hydrogen, methane, and ammonia. From these studies, scientists have concluded that the surface of the primitive Earth was covered with oceans containing the molecules fundamental to life.
Refer the above part to answer Q 24

24. According to the passage, which of the following can be inferred about the process by which the chemical constituents of life were synthesized under primitive Earth conditions?

A. The synthesis is unlikely to occur under current atmospheric conditions. Correct- As the atmospheric condition today is different from that in the past chemical constituents of life is unlikely to occur under current atmospheric condition
B. The synthesis is common in modern laboratories- Completely opposite
C. The synthesis occurs more readily in the atmosphere than in the ocean.-Wrong- The para says the synthesis occurred in ocean and not in atmosphere
D. The synthesis easily produces the most complex organic molecules- Wrong
E. The synthesis is accelerated by the presence of oxygen-containing compounds.- Wrong as the opposite is stated in the passage

Hope this helps!

Hi,


25. The primary purpose of the passage is to


The passage talks mentions 1953 for a reason so as to present the outcome of the research since then.

A. point out that theories about how life developed on Earth have changed little since 1953- Wrong- The author discusses the findings of the experiments since 1953 and not the environmental changes since then.
B. warn of increasing levels of hydrogen, methane, and ammonia in the Earth's atmosphere-Wrong- The author is not warning
C. describe the development since 1953 of some scientists' understanding of how life began on Earth- Correct
D. demonstrate that the synthesis of life in the lab-oratory is too difficult for modern technology- Wrong- Modern technology not discussed
E. describe how primitive atmospheric conditions produced the complex molecules of living organisms- Wrong- it is just a part of the passage and not the primary purpose

26. It can be inferred from the passage that ‘some scientists’ assume which of the following concerning "larger, more complex molecules" (Highlighted)?

In order to answer this question refer the sentence before and after the highlighted portion to get a clearer picture as to what the author is trying to convey.

Although, at present, scientists cannot explain how these relatively small molecules combined to produce larger, more complex molecules, some scientists have precipitously ventured hypotheses that attempt to explain the development, from these larger molecules, of the earliest self-duplicating organisms.

This simply means that although there is no explanation currently as to how the relatively small organism, combined to form a larger one but, according some scientists larger molecules duplicated themselves in to form the smaller molecules.

A. The earliest atmosphere was formed primarily of these molecules.- Wrong- For the above reason
B. Chemical processes involving these molecules proceeded much more slowly under primitive Earth conditions.-Out of Scope
C. The presence of these molecules would necessarily precede the existence of simple organisms.-Correct- Because, as the larger molecules are self duplicating the could have preceded the smaller molecules and produced the smaller molecules by self duplicating
D. Experimental techniques will never be sufficiently sophisticated to produce in the laboratory simple organisms from these chemical constituents.- Out of scope
E. Explanations could easily be developed to explain how simple molecules combined to form these more complex ones.- Huh? Wrong

Hope this helps!

Do let me know if my reasoning for any of the above answers is wrong. I'd appreciate it

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