Basic sleep theory holds that while humans are awake, memories are enc

Question

Basic sleep theory holds that while humans are awake, memories are encoded into our active memory, a process that can lead to temporary synaptic overuse and which eventually leads to tiredness, and that while they are asleep, those memories are consolidated, a process that includes returning synapses to their original state. The molecular cause of tiredness should, therefore, accumulate throughout the day and slowly disappear during sleep. Protein phosphorylation, the process by which proteins are “activated” for use within the cell by the addition of a phosphate group transferred from a molecule called adenosine triphosphate (ATP), maybe this molecular cause. In a recent study, researchers noticed that levels of protein phosphorylation in and around synapses increase during the day while mice are awake and decrease while mice are asleep, suggesting that the hyper-phosphorylation of certain proteins may cause tiredness.

Wang et al. further investigated this hypothesis by comparing the phosphorylation tendencies of regular sleep-deprived mice and of sleep-deprived mice with a single point-mutation in a gene labeled “Sleepy” in order to differentiate between the effects of stress induced by depriving mice of sleep and the effects of natural levels of sleepiness. The Sleepy gene causes sleep frequency and duration to increase, so mice get tired more quickly. Since phosphorylation patterns were consistent between mice with and without the genetic alteration, it is likely that these phosphorylation patterns are indeed at least part of the molecular basis of tiredness.   1 
 B 
 It can be inferred from the passage that the "Sleepy" gene

A. does not occur naturally in mice and is only present when introduced by a scientist.
B. has at least some influence on the extent to which a mouse experiences fatigue.
C. is unrelated to the phosphorylation of protein in mice and other rodents.
D. is more susceptible to mutation than are other genes.
E. decreases the amount of sleep that a mouse requires.

2 
 E 
 It can be inferred from the passage that protein phosphorylation

A. is the primary cause of fatigue in mammals.
B. only occurs when an animal is awake.
C. occurs most frequently when an animal is experiencing stress.
D. occurs less frequently in animals that are nocturnal.
E. takes place in the synapses of the brain.

honneeey · Answer

My explanation-

Cause of tiredness- Accumulation of certain proteins while awake and these same molecules disappear during sleep.
Study conducted-Hyper PP of Certain proteins may cause tiredness.

Further study was conducted to affirm the results.
Between Regular SD mice(depriving mice of sleep) and a mutated "Sleepy" gene mice (natural levels of sleepiness.)
In later case, Mice sleep frequency and duration increases, so they were tired quickly.
BUT, PP patterns were similar in both the types of mice, therefore, PP patterns are somewhere responsible for molecular basis of tiredness.

It can be inferred from the passage that the "Sleepy" gene 
A. does not occur naturally in mice and is only present when introduced by a scientist.-Done for the experiment but no where is it mentioned that it doesnt occur naturally in mice. False
B. has at least some influence on the extent to which a mouse experiences fatigue- Correct, , refer the portion "The Sleepy gene  causes sleep frequency and duration to increase, so mice get tired more quickly "
C. is unrelated to the phosphorylation of protein in mice and other rodents-False, it is related to PP
D. is more susceptible to mutation than are other genes-Out of scope, now here it is mentioned!
E. decreases the amount of sleep that a mouse requires-False, increases the amount of sleep!
 B

It can be inferred from the passage that protein phosphorylation

A. is the primary cause of fatigue in mammals-False"Primary cause" too strong and is not properly substantiated by passage.
B. only occurs when an animal is awake-False, refer " researchers noticed that levels of protein phosphorylation in and around synapses  increase  during the day while mice are awake and decrease while mice are asleep", increase is the word so, only occurs is too strong!
C. occurs most frequently when an animal is experiencing stress -PP is no where directly related to stress in para. False
D. occurs less frequently in animals that are nocturnal.-False, not properly substantiated.
E. takes place in the synapses of the brain.-  Correct  refer "researchers noticed that levels of protein phosphorylation  in and around synapses  "
 E

chibi · Answer

1) It can be inferred from the passage that the "Sleepy" gene

A.  does not occur naturally in mice and is only present when introduced by a scientist . --> Sleepy gene is caused by the genetic mutation and not introduced by the scientists. -  Eliminate (A)

B.  has at least some influence on the extent to which a mouse experiences fatigue.  --> yes. 
Sleepy gene has some influence on the fatigue.   Hold (B)

C.  is unrelated to the phosphorylation of protein in mice and other rodents . --> Reverse answer choice.  Eliminate (C)

D.  is more susceptible to mutation than are other genes.  --> More susceptible is too extreme and not discussed in the passage.  Eliminate(D)

E.  decreases the amount of sleep that a mouse requires.  --> Reverse answer choice.  Eliminate (E)

Clearly (B) is the answer choice

2) It can be inferred from the passage that protein phosphorylation

A.  is the primary cause of fatigue in mammals.  --> Maybe be true. But not given in the passage .  Eliminate(A)

B.  only occurs when an animal is awake.  --> increases when awake and decreases during sleep.  Eliminate(B)

C.  occurs most frequently when an animal is experiencing stress.  --> Not about protein phosphorylation.  Eliminate (C)

D.  occurs less frequently in animals that are nocturnal.  Nocturnal animals are not discussed.  Eliminate (D)

E.  takes place in the synapses of the brain.  Infer from here. Memory(brain)-->Synapse.  Correct

OC2910 · Answer

para1: awake vs asleep ,protien may be the cause
para2 : an experiment to prove protien responsible

Q1:It can be inferred from the passage that the "Sleepy" gene
A. does not occur naturally in mice and is only present when introduced by a scientist.-no mention
 B. has at least some influence on the extent to which a mouse experiences fatigue .-correct refer to second para lines"The Sleepy gene causes sleep frequency and duration to increase, so mice get tired more quickly" 
C. is unrelated to the phosphorylation of protein in mice and other rodents.-- out of scope
D. is more susceptible to mutation than are other genes.-- not mention
E. decreases the amount of sleep that a mouse requires.-- not mentioned

Q2It can be inferred from the passage that protein phosphorylation

A. is the primary cause of fatigue in mammals.--not mentioned and bold(may be a cause but not primary)
B. only occurs when an animal is awake.(passage mentions the amount reduced not eliminated ---gmat tip avoid only)
C. occurs most frequently when an animal is experiencing stress.(the protein is there while sleeping and awake) 
D. occurs less frequently in animals that are nocturnal.(awake vs sleep mentioned not day vs night so eliminate )-wrap answer
E.  takes place in the synapses of the brain .(only option left and is somewhat true as the para 1 )

globaldesi · Answer

For Question 1
Note that whenever you're asked an Inference question, the correct answer must be something that must be true, that is completely proven by the passage. For this reason, be skeptical with categorical/universal statements that might be true (but are not necessarily true) and recognize that certain language (e.g. "some") is just easier to prove.

Here the correct answer is (B): you know from the sentence "the Sleepy gene causes sleep frequency and duration to increase, so mice get tired more quickly" means that the Sleepy gene is involved in how mice experience fatigue, so you can prove that the Sleepy gene "has at least some influence on the extent to which a mouse experiences fatigue."

Note that the other answer choices are all categorical statements that just cannot be definitively proven:

With (A) note the strong language "is only present when introduced by a scientist." You know that scientists altered the Sleepy gene in this experiment, but certainly do not have enough data to conclude that they are the only way that the gene ever appears.

With (C) and (E), the answer choices go in the opposite direction of what's in the passage. (C) says that the Sleepy gene is unrelated to the phosphorylation of protein, but the experiment altered the Sleepy gene in order to better assess protein phosphorylation, so it seems at least likely that it is related (and you do not have information to prove that it is not). And for (E), you're actually told that "the Sleepy gene causes sleep frequency and duration to increase," not to decrease as (E) suggests.

(D) is simply way too broad a statement to prove from the passage. You know that scientists looked at mutations on the Sleepy gene, but have no basis to compare that gene to others.

Answer choice (B) is correct.

globaldesi · Answer

For Question no 2:
Whenever you encounter an Inference question, recognize that the correct answer "must be true" - it needs to be proven - based on the passage. For this reason, be particularly skeptical of answer choices that go just a bit too far: they may be possible based on the passage, but they are not necessarily true.

Choice (A) is a good example: you're told in the middle of paragraph one that "protein phosphorylation...may be the cause" of tiredness, and in the last sentence of the passage that "it is likely that these phosphorylation patterns are indeed at least part of the molecular basis of tiredness." Note that these statements suggest the possibility that (A) is true, but stop well short of proving it to be true.

Choice (B) similarly goes too far by using the extreme language "only": you know from the passage that levels of phosphorylation increase during wakefulness, but this does not mean that the process only occurs during that time.

Choices (C) and (D) simply aren't referenced directly enough in the passage to make a determination about them. With (C) the word "stress" is mentioned but in a different context (scientists compared the stress of being deprived of sleep and the effects of natural fatigue). And with (D) no mention of nocturnal animals is made at all.

Choice (E) must be true. At the end of the first paragraph is the phrase "researchers noticed that levels of protein phosphorylation in and around synapses," which notes that phosphorylation occurs both in and around synapses. Since (E) can be proven based on the passage, it is correct.

abhishekdadarwal2009 · Answer

It can be inferred from the passage that the "Sleepy" gene
 A. does not occur naturally in mice and is only present when introduced by a scientist. Para does not support this hypothesis.
 B. has at least some influence on the extent to which a mouse experiences fatigue. best option, also safe to say that because its not as strong as other options in language.
 C. is unrelated to the phosphorylation of protein in mice and other rodents.  relation is not discussed so we cant be sure.
 D. is more susceptible to mutation than are other genes. mutations is not discussed, so its out of scope.
 E. decreases the amount of sleep that a mouse requires. wrong,no such thing mentioned that the sleepy gene decreass the sleep.

It can be inferred from the passage that protein phosphorylation

A. is the primary cause of fatigue in mammals. it may not be primary casue, its simply related
 B. only occurs when an animal is awake. it occurs more during the awake period and less during sleep.
 C. occurs most frequently when an animal is experiencing stress. stress is not discussed
 D. occurs less frequently in animals that are nocturnal. nocturnal animals are out of scope.
 E. takes place in the synapses of the brain. correct inference.

KS15 · Answer

A. is the primary cause of fatigue in mammals.
B. only occurs when an animal is awake.
C. occurs most frequently when an animal is experiencing stress.
D. occurs less frequently in animals that are nocturnal.
E. takes place in the synapses of the brain.
 E

I disagree with the 2nd answer. It is clearly mentioned in the RC that the process takes place in and around the synapses. So it is not restricted to only 'in' the synapses.
 VeritasKarishma

KarishmaB · Answer

I disagree with the 2nd answer. It is clearly mentioned in the RC that the process takes place in and around the synapses. So it is not restricted to only 'in' the synapses.
 VeritasKarishma

(E) is the best of the given choices. Note that the option doesn't say "it takes place only in the synapses of the brain"
For that matter, it could take place at other places too, not just in and around synapses - we don't know. 
But it does take place in the synapses.

Jashan25 · Answer

In second question I want to understand, when a statement is explicitly mentioned in the passage then how can it be inferred..... it is already mentioned!!!

Basic sleep theory holds that while humans are awake, memories are enc

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Basic sleep theory holds that while humans are awake, memories are enc

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