Dogs are widely employed by the police as biological detection systems

Question

Dogs are widely employed by the police as biological detection systems to detect the smuggling and storage of drugs. Yet, recent evidence suggests that insects, rather than mammals, may be used more effectively in this capacity. One of the disadvantages of dogs lies in the fact that these animals, like humans, may get bored and lose interest. Other problems may also result from the emotional relationship between a dog and its owner. Insects, on the other hand, remain relatively free of these emotional attachments and, at the same time, possess biological detection mechanisms that are at least as effective as those of mammals.

Insects have olfactory systems that are very similar to those of vertebrates, detecting odors via finger-like protuberances on the antenna, called olfactory sensilla. The odorant molecule passes through pores in the outer cuticle of the sensillum and becomes attached to an odorant binding protein. This protein carries the hydrophobic ligand through the lymph fluid found inside the cell and attaches it to a receptor on the dendritic projections of a sensory nerve cell. Finally, this receptor sends a signal to the central nervous system, allowing for easy detection by researchers. The position of the insect olfactory organs on the surface of its body allows for direct investigation of the system’s response. A technique developed by German biologist Dietrich Schneider in the 1950s became the first method that enabled researchers to record the activity in insect olfactory nerves and identify the compounds that trigger a behavioral response. The recent developments in this direction suggest that the detection mechanisms of insects are likely to be applied in practice in the near future.  
 1 
 1. Which of the following statements can be most reasonably inferred from the passage above?

(A) Some police departments have already tested using insects to detect smuggling.
(B) The use of dogs to detect smuggling dates back to the nineteenth century.
(C) Detection of signals sent by the receptors to the central nervous system is easier in insects than in mammals.
(D) In the first half of the twentieth century, there was no reliable method for recording the activity in insect olfactory nerves and identifying the compounds that trigger a behavioral response.
(E) The position of the insect olfactory organs on its body varies between flying insects and crawling insects.

2 
 2. Which of the following most accurately describes the primary purpose of the passage?

(A) To advocate a wider use for the biological detection mechanisms of dogs and other mammals.
(B) To describe possible disadvantages involved in the use of dogs’ biological detection mechanisms.
(C) To describe biological detection mechanisms of insects and suggest that they may provide a viable alternative to those of mammals.
(D) To discuss the process used by insects to detect odors.
(E) To discuss the methods used by biologists to explore insects’ olfactory organs.

3 
 3. It can be inferred from the passage that dogs could be used more effectively in detecting drugs if which of the following were true?

(A) They could last without food for longer periods of time.
(B) They could visually recognize the drugs they are supposed to detect.
(C) They could not only smell but also taste the drugs they are asked to detect.
(D) They could use finger-like protuberances for detecting odors.
(E) They could not develop emotional relationships with people.

4 
 4. Which of the following best describes the author’s attitude towards the prospects of using insects’ biological detection systems in practice?

(A) Moderately optimistic
(B) Completely neutral
(C) Highly doubtful
(D) Largely uninterested
(E) Mildly pessimistic

5 
 5. According to the passage, which of the following roles is played by an odorant binding protein?

(A) It sends a signal to the central nervous system.
(B) It carries the hydrophobic ligand through the lymph fluid and attaches it to a receptor.
(C) It passes through pores in the outer cuticle of the sensillum.
(D) It picks up the signal from the olfactory sensilla.
(E) It transmits odors via finger-like protuberances on the antenna.

6 
 6. It can be inferred from the passage that insects would be less useful for helping researchers to detect drugs if which of the following were true?

(A) They were as accurate as, but not more accurate than, dogs in detecting drugs.
(B) Insect olfactory systems did not deliver odorants to nerve cells in the same way as vertebrate olfactory systems do.
(C) Dietrich Schneider did not develop the first method that enabled researchers to record the activity in insect olfactory nerves.
(D) They did not have finger-like protuberances for detecting odors.
(E) The signal sent to the insect’s central nervous system did not allow researchers to classify the compound that triggered the response.

7 
 Q. 7 According to the passage, researchers are able to capture and investigate an insect’s response to a certain odor because

(A) Researchers have trained insects to respond to different stimuli in different ways
(B) Insects can be used more effectively than dogs to detect certain odors
(C) Insect olfactory systems are similar to vertebrate olfactory systems
(D) The finger-like protuberances on insect antennae are rich in odorant-binding proteins
(E) Insect olfactory organs are located on the surface of an insect’s body

Manhattan CAT 1

pikolo2510 · Accepted Answer

Question 4:-
Please see the last line of the passage
The recent developments in this direction suggest that the detection mechanisms of insects are likely to be applied in practice in the near future
The author is optimistic about Insects in the future.

Now if you see the options,
A. Moderately optimistic
B. Completely neutral
C. Highly doubtful
D. Largely uninterested
E. Mildly pessimistic

Apart from A, all options are negative/neutral. Hence answer should be A

Question 5:-
Please see the below line
This protein carries the hydrophobic ligand through the lymph fluid found inside the cell and attaches it to a receptor on the dendritic projections of a sensory nerve cell

If you check option B in the question, it is just a copy(rephrase) of the above line. Straight away answer should be option B
A. It sends a signal to the central nervous system.
B. It carries the hydrophobic ligand through the lymph fluid and attaches it to a receptor.
C. It passes through pores in the outer cuticle of the sensillum.
D. It picks up the signal from the olfactory sensilla.
E. It transmits odors via finger-like protuberances on the antenna.

Hope this helped

chiragjain507 · Answer

Why not D as the answer for Q6?

Tahamohsin · Answer

Question is asking which one is less helpful for researchers to detect the  DRUGS .
So if answer choice D is true then insects are unable to detect anything.
If E is true then insect does know it's a drug but researcher don't know whether it's a drug or anything else.

Sajjad1994 · Answer

Explanation

First understand what is the demand of the question and then apply your knowledge to find out the answer.

6. It can be inferred from the passage that insects would be less useful for  helping researchers to detect drugs  if which of the following were true?

Explanation

(A)  is irrelevant just to divide your attention from the main question asked.

(B)  seems relevant but not in the direction we are looking in. This is not mentioned in the passage that Insect olfactory systems  must  deliver odorants to nerve cells in the same way as vertebrate olfactory systems do to detect drugs so B is wrong.

(C)  is again irrelevant.

(D)  is just opposing the fact given in the passage, it is trap answer. One thing is mentioned in the passage but answer choice just negating that fact.

(E)  matches the requirement of the question. In  lines 18-19   (Finally, this receptor sends a signal to the central nervous system, allowing for easy detection by researchers.)  the answer could be found. Here the word Classify is very important.

The signal sent to the insect’s central nervous system did not allow researchers to   classify   the compound that triggered the response. It means it is not negating the fact rather given us a direction that why insects would be less useful.

Answer: E

Hope it helps

Thelionking1234 · Answer

OFFICIAL EXPLANATION Q.7 
 
According to the passage means that this is a  Specific Detail  question. The use of insects to detect drugs has two important components: an insect’s olfactory systems must first be able to detect such drugs, and then researchers must be able to capture and use the insect’s responses. The fourth sentence of the first paragraph states that the position of the insect olfactory organs on the surface of its body allows for direct investigation of the system’s response. The last sentence of the second paragraph also says that signals are sent to the central nervous system, allowing researchers to detect and interpret the responses. The correct answer should account for one or both of these statements.

(A) The passage does not mention anything about the researchers training insects to respond in certain ways.

(B) The passage does say that insects might be used more effectively than dogs in detecting drugs, but this is not why researchers are able to interpret an insect’s response to a certain odor. Rather, the reverse is true: because researchers are able to interpret an insect’s responses, the insects may be reliably used to detect drugs.

(C) The passage does say, at the beginning of paragraph two, that insect olfactory systems are very similar to vertebrate olfactory systems, but the passage does not indicate that this is why researchers are able to interpret an insect’s response to certain odors. Rather, the information at the end of the first and second paragraphs indicates why researchers are able to do this.

(D) The passage states that insects first detect odors via finger-like protuberances on the antenna and that these odorant molecules pass through pores into the antenna, where they become attached to an odorant-binding protein. The passage does not indicate that the finger-like protuberances are rich in these odorant-binding proteins.

(E) CORRECT. The fourth sentence of the first paragraph states that the position of the insect olfactory organs on the surface of its body allows for direct investigation of the system’s response. This is why the researchers can capture and investigate an insect’s responses.

Sajjad1994 · Answer

Official Explanation

6. It can be inferred from the passage that insects would be less useful for helping researchers to detect drugs if which of the following were true?

Explanation

The words can be inferred indicate an Inference question, and the words would be and if which of the following were true suggest an inference about a hypothetical situation. The first paragraph introduces a research method that allows researchers to record activity in insect nerves and identify the compounds that triggered the activity (in other words, to detect certain drugs). In the last sentence of the second paragraph, the author says that signals sent to the central nervous system allow researchers to detect and interpret the responses. In other words, the researchers detect a signal sent to the central nervous system and are then able to identify what compound triggered that signal. If the researchers were not able to do these things, the insects would be less useful for the purpose of detecting drugs.

(A)  The passage establishes that dogs are already widely used to detect drugs and then claims that insects might be used more effectively than mammals. This does not imply that insects would be less useful if they are only as accurate as dogs; indeed, according to the passage, the insects may not be more accurate than dogs in detecting drugs.

(B)  The passage does indicate that there are similarities between the olfactory systems of insects and dogs. However, the passage doesn’t say that the two systems must work in the same way in order for insects to be useful; the two olfactory systems could be different and yet the insects could still be useful.

(C)  The passage does not indicate that the method is more useful because it was discovered by Dietrich Schneider. It might have been just as useful no matter who discovered it.

(D)  The passage does not indicate that the insects are only useful for detecting drugs because they detect odors via finger-like protuberances. Any mechanism might work as long as it allowed a certain signal to be sent that could then be detected by the researchers and tied to a specific source compound.

(E)  CORRECT.   According to the passage, the signal sent by the central nervous system is easily detected by researchers and allows them to identify which compounds triggered that signal. If the researchers were not actually able to classify which compound or type of compound triggered that signal, then the insects would not be as useful; the researchers would not necessarily be able to tell whether illegal drugs or something innocuous had been detected by the insect.

Answer: E

Sajjad1994 · Answer

Official Explanation

2. Which of the following most accurately describes the primary purpose of the passage?

Explanation

The words primary purpose indicate that this is a Main Idea question. The first paragraph mentions that dogs are currently used to detect drugs, that insects may be better than dogs, and that a researcher developed a scientific method to test insects for this purpose. The second paragraph describes in significant detail how that scientific method works.

(A)  The passage does say that insects might be used more effectively than dogs in detecting drugs, but the author never suggests that insects should replace dogs in this job.

(B)  The passage does discuss the advantages to researchers of a particular biological mechanism, but does not discuss disadvantages.

(C)  CORRECT.   The passage does describe, in the second paragraph, a particular biological mechanism (how insects detect odors). The first paragraph does indicate how this biological mechanism might be exploited (to detect drugs).

(D)  While the second paragraph of the passage does discuss how a type of organism (insects) detects odors, this by itself cannot be considered the primary purpose of the passage. The mechanism by which insects detect odors is discussed in order to provide support for the primary claim: that insects might be used effectively, possibly more effectively than dogs, to detect drugs.

(E)  The first paragraph does mention Dietrich Schneider’s contribution to the topic at hand (how researchers can use insects to detect drugs), but the passage does not summarize the entire history of Schneider’s research contributions throughout his career.

Answer: C

VerbalBot · Answer

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Dogs are widely employed by the police as biological detection systems

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Dogs are widely employed by the police as biological detection systems

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