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Test: Reading Comprehension: Bio Sciences - GMAT MCQ


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20 Questions MCQ Test - Test: Reading Comprehension: Bio Sciences

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Test: Reading Comprehension: Bio Sciences - Question 1

A team of researchers has been able to successfully study the highly complex molecular structure of mitoribosomes, which are the ribosomes of mitochondria. Ribosomes are found in the cells of all living organisms, and they serve as a primary location for biological protein synthesis, but certain organisms such as fungi, plants, animals, and humans contain much more complex ribosomes than bacteria do. In organisms with complex cells, ribosomes can also be divided into two types: those in the cytosol -- which comprises the majority of the cell -- and those found in the mitochondria or "power houses" of cells. Mitochondria are found only in eukaryotes. Every ribosome consists of two subunits. The smaller subunit uses transfer ribonucleic acids to decode the genetic code, which is stored in the DNA, it receives in the form of messenger ribonucleic acids, while the larger subunit joins the amino acids delivered by the transfer ribonucleic acids together like a string of pearls. 

Since they are found only in small amounts and are difficult to isolate, mitochondrial ribosomes or mitoribosomes are particularly difficult to study.  But because of the recent technical advances in cryo-electron microscopy and the development of direct electron detection cameras that can correct for specimen motion during the exposure, it recently became possible to capture images of biomolecules at a resolution high enough to capture the details, especially those of the peptidyl transferase centre (PTC).

This research is of special importance to producing the right kind of antibiotics for humans. PTC is where the amino acid building blocks are combined, leading to protein synthesis. As per the researchers, this process of synthesizing proteins is medically relevant as the tunnel through which the proteins pass, after being synthesized, is a target for specific antibiotics. The antibiotic blocks the tunnel, preventing the proteins that have just been synthesized from leaving the tunnel. However, for an antibiotic to be used in humans, it must not attack human ribosomes and should inhibit protein synthesis only in the ribosomes of bacteria.  The problem arises since mitochondrial ribosomes resemble those of bacteria, which is why certain antibiotics also interfere with mitoribosomes, possibly leading to serious side effects. The findings of the research will make it possible in the future to design antibiotics that inhibit only bacterial and not mitochondrial ribosomes, the one basic requirement for using them in clinical applications.

The author is primarily concerned with

Detailed Solution for Test: Reading Comprehension: Bio Sciences - Question 1

Passage Analysis

 

Summary and Main Point

 

Pre-Thinking

This is a Main Idea question. The correct answer must be broad enough to encompass all the content of the passage without veering outside the scope.

The first paragraph talks about an achievement and sets the context for the same. The second paragraph explains how this achievement was made possible. The last paragraph deals with the relevance of the achievement and use of antibiotics on humans. The correct answer must incorporate all these points.

Answer Choices

A

To encapsulate the significance of a key medical research

Incorrect: Partial scope

Although this is the scope of the final paragraph, this choice does not capture the essence of the first two paragraphs.

B

To evaluate the achievements and failure of a study undertaken to understand the workings of antibiotics on humans

Incorrect: Out Of Context

There is no mention of any kind of failure of the research. Secondly, this choice does not even talk about the context of the first paragraph.

C

To educate the reader about the functions of certain parts and how certain antibiotics can be harmful to these parts

Incorrect: Irrelevant

Although this choice describes the details mentioned in two out of the three paragraphs of the passage, it fails to present the broader picture or reason for which the author presents the details; for instance, the talk about the effect of the antibiotics is to discuss the relevance of the findings of the research and not just educate the readers about the harmful effects of the antibiotics.

D

To discuss the relevance of a research while setting the context for it

Correct

This choice matches the main point we came up with earlier. The first two paragraphs set the context for the research by educating the reader about the medical terms involved and how the study was able to reach its findings, while the last paragraphs discusses the significance of the findings of the research.

E

To describe a key medical finding while discussing some of the key problems faced by the pharmaceutical companies

Incorrect: Irrelevant

The author does more than just “describe” a finding of the research. He/she sets the context for the research in the first two paragraphs and discusses the relevance of the research in the last paragraph. This choice fails to capture the breadth of the work done by the author in the passage. Plus, there is no mention of the problems faced by the pharmaceutical companies.

Test: Reading Comprehension: Bio Sciences - Question 2

A team of researchers has been able to successfully study the highly complex molecular structure of mitoribosomes, which are the ribosomes of mitochondria. Ribosomes are found in the cells of all living organisms, and they serve as a primary location for biological protein synthesis, but certain organisms such as fungi, plants, animals, and humans contain much more complex ribosomes than bacteria do. In organisms with complex cells, ribosomes can also be divided into two types: those in the cytosol -- which comprises the majority of the cell -- and those found in the mitochondria or "power houses" of cells. Mitochondria are found only in eukaryotes. Every ribosome consists of two subunits. The smaller subunit uses transfer ribonucleic acids to decode the genetic code, which is stored in the DNA, it receives in the form of messenger ribonucleic acids, while the larger subunit joins the amino acids delivered by the transfer ribonucleic acids together like a string of pearls. 

Since they are found only in small amounts and are difficult to isolate, mitochondrial ribosomes or mitoribosomes are particularly difficult to study.  But because of the recent technical advances in cryo-electron microscopy and the development of direct electron detection cameras that can correct for specimen motion during the exposure, it recently became possible to capture images of biomolecules at a resolution high enough to capture the details, especially those of the peptidyl transferase centre (PTC).

This research is of special importance to producing the right kind of antibiotics for humans. PTC is where the amino acid building blocks are combined, leading to protein synthesis. As per the researchers, this process of synthesizing proteins is medically relevant as the tunnel through which the proteins pass, after being synthesized, is a target for specific antibiotics. The antibiotic blocks the tunnel, preventing the proteins that have just been synthesized from leaving the tunnel. However, for an antibiotic to be used in humans, it must not attack human ribosomes and should inhibit protein synthesis only in the ribosomes of bacteria.  The problem arises since mitochondrial ribosomes resemble those of bacteria, which is why certain antibiotics also interfere with mitoribosomes, possibly leading to serious side effects. The findings of the research will make it possible in the future to design antibiotics that inhibit only bacterial and not mitochondrial ribosomes, the one basic requirement for using them in clinical applications.

Which of the following can be inferred from the passage?

Detailed Solution for Test: Reading Comprehension: Bio Sciences - Question 2

Passage Analysis

 

Summary and Main Point

 

Pre-Thinking

This is an Inference question. The correct answer will either be a restatement of what’s given in the passage or be a statement that can be deduced on the basis of the given information but may not be itself be explicitly stated in the passage. Negate the answer choices that are not bolstered by specific facts mentioned in the passage.

Answer Choices

A

The same antibiotic will have different reactions on humans and animals.

Incorrect: Out Of Scope

There is no information given in the passage about the comparative action of any antibiotic on humans and animals.

B

The pharmaceutical companies that have been producing antibiotics that inadvertently harm people by blocking the release of the proteins will gain significant monetary benefit from producing antibiotics that do not attack the human body in such a way.

Incorrect: Out Of Scope

To begin with, there is no mention of any pharmaceutical companies. Yes, the author talks about how the research could lead to the development of better (less harmful) antibiotics but there is no information given in the passage to support that such companies will gain significantly in monetary terms by developing them.

C

The quantity of a specific kind of ribosomes was partly responsible for the limited success in studying them.

Correct

This choice is a combination of a couple of statements from the passage. The author tells us that mitoribosomes are ribosomes of a specific kind (first paragraph) and that they are particularly difficult to study because they are found only in small amounts and are difficult to isolate (second paragraph). Hence, one can infer the information given in this choice.

D

Without the latest technical advances in cryo- electron microscopy, it would not have been possible to study mitoribosomes at all.

Incorrect: Out Of Scope

All the author tells us is how this advancement enabled the researcher to capture certain details for the first time. However, it gives us no ground to infer that the study of mitoribosomes itself would have been impossible or that before the study, there was no information available on them.

E

Mitoribosomes are the only kind of ribosomes that are adversely affected by antibiotics.

Incorrect: Out Of Scope

There is no information given in the passage to conclude that the antibiotics do not have any adverse effect on other kinds of ribosomes.

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Test: Reading Comprehension: Bio Sciences - Question 3

A team of researchers has been able to successfully study the highly complex molecular structure of mitoribosomes, which are the ribosomes of mitochondria. Ribosomes are found in the cells of all living organisms, and they serve as a primary location for biological protein synthesis, but certain organisms such as fungi, plants, animals, and humans contain much more complex ribosomes than bacteria do. In organisms with complex cells, ribosomes can also be divided into two types: those in the cytosol -- which comprises the majority of the cell -- and those found in the mitochondria or "power houses" of cells. Mitochondria are found only in eukaryotes. Every ribosome consists of two subunits. The smaller subunit uses transfer ribonucleic acids to decode the genetic code, which is stored in the DNA, it receives in the form of messenger ribonucleic acids, while the larger subunit joins the amino acids delivered by the transfer ribonucleic acids together like a string of pearls. 

Since they are found only in small amounts and are difficult to isolate, mitochondrial ribosomes or mitoribosomes are particularly difficult to study.  But because of the recent technical advances in cryo-electron microscopy and the development of direct electron detection cameras that can correct for specimen motion during the exposure, it recently became possible to capture images of biomolecules at a resolution high enough to capture the details, especially those of the peptidyl transferase centre (PTC).

This research is of special importance to producing the right kind of antibiotics for humans. PTC is where the amino acid building blocks are combined, leading to protein synthesis. As per the researchers, this process of synthesizing proteins is medically relevant as the tunnel through which the proteins pass, after being synthesized, is a target for specific antibiotics. The antibiotic blocks the tunnel, preventing the proteins that have just been synthesized from leaving the tunnel. However, for an antibiotic to be used in humans, it must not attack human ribosomes and should inhibit protein synthesis only in the ribosomes of bacteria.  The problem arises since mitochondrial ribosomes resemble those of bacteria, which is why certain antibiotics also interfere with mitoribosomes, possibly leading to serious side effects. The findings of the research will make it possible in the future to design antibiotics that inhibit only bacterial and not mitochondrial ribosomes, the one basic requirement for using them in clinical applications.

Which of the following is mentioned in the passage?

Detailed Solution for Test: Reading Comprehension: Bio Sciences - Question 3

Passage Analysis

 

Summary and Main Point

 

Pre-Thinking

This is a Detail question. Keep crossing out answer choices that are not explicitly stated in the passage and choose the one for which you can directly refer to a portion in the passage.

Answer Choices

A

The attack on human ribosomes by certain antibiotics could prove fatal.

Incorrect: Inconsistent

The author states that such attacks could have serious side effects, but nowhere does he/she say that these effects could be lethal.

B

Ribosomes are solely responsible for producing protein in the body.

Incorrect: Inconsistent

In the first paragraph, it is stated that ribosomes are primarily and not solely responsible for protein synthesis.

C

Ribosomes are defenseless against the attack launched by certain antibiotics on them.

Incorrect: Out Of Scope

How ribosomes react when they are attacked by antibiotics is not given in the passage; hence, this choice is not supported by the given information.

D

All living organisms have ribosomes that can be divided in to two types.

Incorrect: Inconsistent

In the first paragraph, we are told that all living organisms have ribosomes but only the ribosomes in complex celled organisms can be divided into two types.

E

Ribosomes in humans are not as simple as the ones found in bacteria.

Correct

This information is stated in the first paragraph. Please refer to the following extract below:

… certain organisms such as fungi, plants, animals and humans, contain much more complex ribosomes than bacteria.

Test: Reading Comprehension: Bio Sciences - Question 4

A team of researchers has been able to successfully study the highly complex molecular structure of mitoribosomes, which are the ribosomes of mitochondria. Ribosomes are found in the cells of all living organisms, and they serve as a primary location for biological protein synthesis, but certain organisms such as fungi, plants, animals, and humans contain much more complex ribosomes than bacteria do. In organisms with complex cells, ribosomes can also be divided into two types: those in the cytosol -- which comprises the majority of the cell -- and those found in the mitochondria or "power houses" of cells. Mitochondria are found only in eukaryotes. Every ribosome consists of two subunits. The smaller subunit uses transfer ribonucleic acids to decode the genetic code, which is stored in the DNA, it receives in the form of messenger ribonucleic acids, while the larger subunit joins the amino acids delivered by the transfer ribonucleic acids together like a string of pearls. 

Since they are found only in small amounts and are difficult to isolate, mitochondrial ribosomes or mitoribosomes are particularly difficult to study.  But because of the recent technical advances in cryo-electron microscopy and the development of direct electron detection cameras that can correct for specimen motion during the exposure, it recently became possible to capture images of biomolecules at a resolution high enough to capture the details, especially those of the peptidyl transferase centre (PTC).

This research is of special importance to producing the right kind of antibiotics for humans. PTC is where the amino acid building blocks are combined, leading to protein synthesis. As per the researchers, this process of synthesizing proteins is medically relevant as the tunnel through which the proteins pass, after being synthesized, is a target for specific antibiotics. The antibiotic blocks the tunnel, preventing the proteins that have just been synthesized from leaving the tunnel. However, for an antibiotic to be used in humans, it must not attack human ribosomes and should inhibit protein synthesis only in the ribosomes of bacteria.  The problem arises since mitochondrial ribosomes resemble those of bacteria, which is why certain antibiotics also interfere with mitoribosomes, possibly leading to serious side effects. The findings of the research will make it possible in the future to design antibiotics that inhibit only bacterial and not mitochondrial ribosomes, the one basic requirement for using them in clinical applications.

Which of the following most aptly describes the function of the first paragraph?

Detailed Solution for Test: Reading Comprehension: Bio Sciences - Question 4

Passage Analysis

 

Summary and Main Point

 

Pre-Thinking

This is a Function question.

From the individual paragraph summaries, we know that the first paragraph mentions an achievement and sets the context for the same. This is the function of the first paragraph.

Answer Choices

A

To discuss the overall functioning of the human body

Incorrect: Inconsistent

The author does mention the functions of ribosomes and mitochondria, but this information is not given from the viewpoint of discussing the overall functioning of the human body. It’s given from the point of view of setting the context for the research mentioned in the passage.

B

To explain the scope of relevance of the mentioned research

Incorrect: Irrelevant

Any discussion on the relevance of the research is found in the third final paragraph, not in the first one.

C

To give details about two unrelated concepts

Incorrect: Irrelevant

All the pieces of information given in the first paragraph about ribosomes and mitochondria are related to one another.

D

To mention an achievement while setting the context for it

Correct

This choice matches the function we came up with in the passage analysis. The discussion on ribosomes and mitochondria is related to the discussion the author wants to hold for the achievement of the researchers. Hence, the author sets context for it by educating the reader about ribosomes and mitochondria.

E

To provide information about ribosomes particularly about mitoribosomes

Incorrect: Partial Scope

The paragraph does provide information about ribosomes but never focuses on mitoribosomes in terms of sharing details on them. Also, whatever the details are, they are meant as part of a discussion in which they set context for the mentioned medical research.

Test: Reading Comprehension: Bio Sciences - Question 5

Despite radical differences in what limbs do and what they look like, the underlying blueprint of all limbs in land based animals, whether those limbs are wings in birds, flippers in penguins, or hands in humans, is the same - one bone, the humerus in the arm or the femur in the leg, articulates with two bones, which attach to a series of small blobs, which connect with the fingers or toes. Want to make a bat wing? Make the fingers really long. Want to make a horse? Elongate the middle fingers and toes and  lose the outer ones. The differences between creatures lie in differences in the shapes and sizes of the bones and the numbers of blobs, fingers, and toes.

In the 1950s and 1960s a number of biologists, including Edgar Zwilling and John Saunders, did extraordinarily creative experiments on chicken eggs to understand how skeletal structure of limbs  forms and uncovered some of the key mechanisms that build limbs that have the same architecture but are as different as bird wings, lizards webbings,  and human hands .  They discovered that two little patches of tissue essentially control the development of the pattern of bones inside limbs. These patches of tissue were named the zone of polarizing activity (ZPA). The cells in the ZPA made special molecules that then spread across the limb to instruct cells to make femur, articulates, and connecting toes. The concentration of these molecules was the important factor and decided the length of femur, articulates, connecting toes, and even the length of individual toe fingers. Later experiments with other animals such as the bat, frog, etc. proved that the mechanism to form limbs remained the same - formation of limbs in every creature was controlled by the ZPA – just the concentration of these special molecules varied corresponding to the desired structure.

The reason for this inherent commonality in architecture still remained a conundrum for decades. Why did nature not develop architectures better optimized to the functional needs of various organisms? The discovery of Tiktaalik, a transition between non-tetrapod vertebrates ("fish") to early tetrapods solved this mystery, providing evidence that all land based creatures that have limbs, hands, etc. share a common ancestor. The fact that our DNA and that of all land based animals can be traced back to Tiktaalik further provided evidence  that all appendages, whether they are hands or limbs, are built by similar kinds of genes and that this great evolutionary transformation did not involve the origin of new DNA: much of the shift likely involved using ancient genes, such as those involved in development of Tiktaalik’s limbs, in new ways to make wings in birds or various sized limbs with fingers and toes, explaining the diversity in shapes while maintaining the similarity in architecture. 

According to the passage the mechanism that builds limbs as different as bird wings, penguin flippers, and human hands etc. is 

 

Test: Reading Comprehension: Bio Sciences - Question 6

Despite radical differences in what limbs do and what they look like, the underlying blueprint of all limbs in land based animals, whether those limbs are wings in birds, flippers in penguins, or hands in humans, is the same - one bone, the humerus in the arm or the femur in the leg, articulates with two bones, which attach to a series of small blobs, which connect with the fingers or toes. Want to make a bat wing? Make the fingers really long. Want to make a horse? Elongate the middle fingers and toes and  lose the outer ones. The differences between creatures lie in differences in the shapes and sizes of the bones and the numbers of blobs, fingers, and toes.

In the 1950s and 1960s a number of biologists, including Edgar Zwilling and John Saunders, did extraordinarily creative experiments on chicken eggs to understand how skeletal structure of limbs  forms and uncovered some of the key mechanisms that build limbs that have the same architecture but are as different as bird wings, lizards webbings,  and human hands .  They discovered that two little patches of tissue essentially control the development of the pattern of bones inside limbs. These patches of tissue were named the zone of polarizing activity (ZPA). The cells in the ZPA made special molecules that then spread across the limb to instruct cells to make femur, articulates, and connecting toes. The concentration of these molecules was the important factor and decided the length of femur, articulates, connecting toes, and even the length of individual toe fingers. Later experiments with other animals such as the bat, frog, etc. proved that the mechanism to form limbs remained the same - formation of limbs in every creature was controlled by the ZPA – just the concentration of these special molecules varied corresponding to the desired structure.

The reason for this inherent commonality in architecture still remained a conundrum for decades. Why did nature not develop architectures better optimized to the functional needs of various organisms? The discovery of Tiktaalik, a transition between non-tetrapod vertebrates ("fish") to early tetrapods solved this mystery, providing evidence that all land based creatures that have limbs, hands, etc. share a common ancestor. The fact that our DNA and that of all land based animals can be traced back to Tiktaalik further provided evidence  that all appendages, whether they are hands or limbs, are built by similar kinds of genes and that this great evolutionary transformation did not involve the origin of new DNA: much of the shift likely involved using ancient genes, such as those involved in development of Tiktaalik’s limbs, in new ways to make wings in birds or various sized limbs with fingers and toes, explaining the diversity in shapes while maintaining the similarity in architecture. 

In the context of the passage, why was the discovery of the Tiktaalik important? 

Test: Reading Comprehension: Bio Sciences - Question 7

Despite radical differences in what limbs do and what they look like, the underlying blueprint of all limbs in land based animals, whether those limbs are wings in birds, flippers in penguins, or hands in humans, is the same - one bone, the humerus in the arm or the femur in the leg, articulates with two bones, which attach to a series of small blobs, which connect with the fingers or toes. Want to make a bat wing? Make the fingers really long. Want to make a horse? Elongate the middle fingers and toes and  lose the outer ones. The differences between creatures lie in differences in the shapes and sizes of the bones and the numbers of blobs, fingers, and toes.

In the 1950s and 1960s a number of biologists, including Edgar Zwilling and John Saunders, did extraordinarily creative experiments on chicken eggs to understand how skeletal structure of limbs  forms and uncovered some of the key mechanisms that build limbs that have the same architecture but are as different as bird wings, lizards webbings,  and human hands .  They discovered that two little patches of tissue essentially control the development of the pattern of bones inside limbs. These patches of tissue were named the zone of polarizing activity (ZPA). The cells in the ZPA made special molecules that then spread across the limb to instruct cells to make femur, articulates, and connecting toes. The concentration of these molecules was the important factor and decided the length of femur, articulates, connecting toes, and even the length of individual toe fingers. Later experiments with other animals such as the bat, frog, etc. proved that the mechanism to form limbs remained the same - formation of limbs in every creature was controlled by the ZPA – just the concentration of these special molecules varied corresponding to the desired structure.

The reason for this inherent commonality in architecture still remained a conundrum for decades. Why did nature not develop architectures better optimized to the functional needs of various organisms? The discovery of Tiktaalik, a transition between non-tetrapod vertebrates ("fish") to early tetrapods solved this mystery, providing evidence that all land based creatures that have limbs, hands, etc. share a common ancestor. The fact that our DNA and that of all land based animals can be traced back to Tiktaalik further provided evidence  that all appendages, whether they are hands or limbs, are built by similar kinds of genes and that this great evolutionary transformation did not involve the origin of new DNA: much of the shift likely involved using ancient genes, such as those involved in development of Tiktaalik’s limbs, in new ways to make wings in birds or various sized limbs with fingers and toes, explaining the diversity in shapes while maintaining the similarity in architecture. 

From the passage, what can be inferred about the architecture of limbs?

Test: Reading Comprehension: Bio Sciences - Question 8

Despite radical differences in what limbs do and what they look like, the underlying blueprint of all limbs in land based animals, whether those limbs are wings in birds, flippers in penguins, or hands in humans, is the same - one bone, the humerus in the arm or the femur in the leg, articulates with two bones, which attach to a series of small blobs, which connect with the fingers or toes. Want to make a bat wing? Make the fingers really long. Want to make a horse? Elongate the middle fingers and toes and  lose the outer ones. The differences between creatures lie in differences in the shapes and sizes of the bones and the numbers of blobs, fingers, and toes.In the 1950s and 1960s a number of biologists, including Edgar Zwilling and John Saunders, did extraordinarily creative experiments on chicken eggs to understand how skeletal structure of limbs  forms and uncovered some of the key mechanisms that build limbs that have the same architecture but are as different as bird wings, lizards webbings,  and human hands .  They discovered that two little patches of tissue essentially control the development of the pattern of bones inside limbs. These patches of tissue were named the zone of polarizing activity (ZPA). The cells in the ZPA made special molecules that then spread across the limb to instruct cells to make femur, articulates, and connecting toes. The concentration of these molecules was the important factor and decided the length of femur, articulates, connecting toes, and even the length of individual toe fingers. Later experiments with other animals such as the bat, frog, etc. proved that the mechanism to form limbs remained the same - formation of limbs in every creature was controlled by the ZPA – just the concentration of these special molecules varied corresponding to the desired structure.The reason for this inherent commonality in architecture still remained a conundrum for decades. Why did nature not develop architectures better optimized to the functional needs of various organisms? The discovery of Tiktaalik, a transition between non-tetrapod vertebrates ("fish") to early tetrapods solved this mystery, providing evidence that all land based creatures that have limbs, hands, etc. share a common ancestor. The fact that our DNA and that of all land based animals can be traced back to Tiktaalik further provided evidence  that all appendages, whether they are hands or limbs, are built by similar kinds of genes and that this great evolutionary transformation did not involve the origin of new DNA: much of the shift likely involved using ancient genes, such as those involved in development of Tiktaalik’s limbs, in new ways to make wings in birds or various sized limbs with fingers and toes, explaining the diversity in shapes while maintaining the similarity in architecture. 

The primary purpose of the passage is 

Test: Reading Comprehension: Bio Sciences - Question 9

Tit-for-Tat – a strategy that is a variation of an eye for an eye and a tooth for a tooth - is clear and simple, never initiates cheating, and provocable that it is, it never allows cheating to go unpunished.  It is surprisingly successful in two-person prisoner’s dilemma games. In a tournament that pitched 150 game theorists from around the world and in which contestants were ranked by the sum of their scores, the winner Anatol Rapoport successfully deployed this strategy. The result and the winner remained the same when the same tournament was repeated with an expanded audience.  One of the impressive features about Tit-for-Tat is that it did so well overall, even though it did not (nor could it) beat any one of its rivals in a head-on. At best, Tit-for-Tat ties its rivals. Hence, if the competition was scored as a winner take-all contest, Anatol would not have won. The two advantages of Tit-for-Tat are that firstly, it always comes close and secondly, it usually encourages cooperation while avoiding exploitation.

In-spite of the above, Tit-for-Tat is a flawed strategy in certain situations. The slightest possibility of misperception results in the complete breakdown in the success of Tit-for-Tat. For example, in 1987, the United States responded to the Soviet spying and wiretapping of the US embassy in Moscow by reducing the number of Soviet diplomats permitted in United States. The Soviets responded by cutting the support staff at the US embassy in Moscow and reducing the number of US diplomats. As a result, both countries found it difficult to carry on their diplomatic functions.  The problem with Tit-for-Tat is that any mistake echoes back and forth and sets up a chain reaction that has the potential to cause grave damage.

The passage suggests that Anatol Rapoport won the two-person prisoner’s dilemma tournaments because

Test: Reading Comprehension: Bio Sciences - Question 10

Tit-for-Tat – a strategy that is a variation of an eye for an eye and a tooth for a tooth - is clear and simple, never initiates cheating, and provocable that it is, it never allows cheating to go unpunished.  It is surprisingly successful in two-person prisoner’s dilemma games. In a tournament that pitched 150 game theorists from around the world and in which contestants were ranked by the sum of their scores, the winner Anatol Rapoport successfully deployed this strategy. The result and the winner remained the same when the same tournament was repeated with an expanded audience.  One of the impressive features about Tit-for-Tat is that it did so well overall, even though it did not (nor could it) beat any one of its rivals in a head-on. At best, Tit-for-Tat ties its rivals. Hence, if the competition was scored as a winner take-all contest, Anatol would not have won. The two advantages of Tit-for-Tat are that firstly, it always comes close and secondly, it usually encourages cooperation while avoiding exploitation.

In-spite of the above, Tit-for-Tat is a flawed strategy in certain situations. The slightest possibility of misperception results in the complete breakdown in the success of Tit-for-Tat. For example, in 1987, the United States responded to the Soviet spying and wiretapping of the US embassy in Moscow by reducing the number of Soviet diplomats permitted in United States. The Soviets responded by cutting the support staff at the US embassy in Moscow and reducing the number of US diplomats. As a result, both countries found it difficult to carry on their diplomatic functions.  The problem with Tit-for-Tat is that any mistake echoes back and forth and sets up a chain reaction that has the potential to cause grave damage.

What can be inferred about the two-person prisoner’s dilemma tournaments discussed in the passage?

Test: Reading Comprehension: Bio Sciences - Question 11

Tit-for-Tat – a strategy that is a variation of an eye for an eye and a tooth for a tooth - is clear and simple, never initiates cheating, and provocable that it is, it never allows cheating to go unpunished.  It is surprisingly successful in two-person prisoner’s dilemma games. In a tournament that pitched 150 game theorists from around the world and in which contestants were ranked by the sum of their scores, the winner Anatol Rapoport successfully deployed this strategy. The result and the winner remained the same when the same tournament was repeated with an expanded audience.  One of the impressive features about Tit-for-Tat is that it did so well overall, even though it did not (nor could it) beat any one of its rivals in a head-on. At best, Tit-for-Tat ties its rivals. Hence, if the competition was scored as a winner take-all contest, Anatol would not have won. The two advantages of Tit-for-Tat are that firstly, it always comes close and secondly, it usually encourages cooperation while avoiding exploitation.

In-spite of the above, Tit-for-Tat is a flawed strategy in certain situations. The slightest possibility of misperception results in the complete breakdown in the success of Tit-for-Tat. For example, in 1987, the United States responded to the Soviet spying and wiretapping of the US embassy in Moscow by reducing the number of Soviet diplomats permitted in United States. The Soviets responded by cutting the support staff at the US embassy in Moscow and reducing the number of US diplomats. As a result, both countries found it difficult to carry on their diplomatic functions.  The problem with Tit-for-Tat is that any mistake echoes back and forth and sets up a chain reaction that has the potential to cause grave damage.

What can be inferred about the two-person prisoner’s dilemma tournaments discussed in the passage?

Test: Reading Comprehension: Bio Sciences - Question 12

Tit-for-Tat – a strategy that is a variation of an eye for an eye and a tooth for a tooth - is clear and simple, never initiates cheating, and provocable that it is, it never allows cheating to go unpunished.  It is surprisingly successful in two-person prisoner’s dilemma games. In a tournament that pitched 150 game theorists from around the world and in which contestants were ranked by the sum of their scores, the winner Anatol Rapoport successfully deployed this strategy. The result and the winner remained the same when the same tournament was repeated with an expanded audience.  One of the impressive features about Tit-for-Tat is that it did so well overall, even though it did not (nor could it) beat any one of its rivals in a head-on. At best, Tit-for-Tat ties its rivals. Hence, if the competition was scored as a winner take-all contest, Anatol would not have won. The two advantages of Tit-for-Tat are that firstly, it always comes close and secondly, it usually encourages cooperation while avoiding exploitation.

In-spite of the above, Tit-for-Tat is a flawed strategy in certain situations. The slightest possibility of misperception results in the complete breakdown in the success of Tit-for-Tat. For example, in 1987, the United States responded to the Soviet spying and wiretapping of the US embassy in Moscow by reducing the number of Soviet diplomats permitted in United States. The Soviets responded by cutting the support staff at the US embassy in Moscow and reducing the number of US diplomats. As a result, both countries found it difficult to carry on their diplomatic functions.  The problem with Tit-for-Tat is that any mistake echoes back and forth and sets up a chain reaction that has the potential to cause grave damage.

According to the passage, the reason why both US and Soviet embassies found it difficult to carry on their diplomatic functions is

Test: Reading Comprehension: Bio Sciences - Question 13

Sea turtles, reptilian amphibians that are classified into seven distinct sub-species, are quickly beginning to rank among some of the most endangered species on the planet. These ancient reptiles are vital to Earth’s ecosystem because they feed on botanical life that grows on sea beds and thereby help maintain the natural habitat of several other marine life forms. Further, unhatched sea turtle eggs provide nutrients for plants that grow beneath the surface of the sea, which in turn strengthen sand dunes through their root systems and help prevent beaches from eroding.

Ironically, human attempts to preserve the marine environment in which sea turtles live are causing the species’ numbers to dwindle even faster. In an effort to protect sea turtles that nest on the beaches,  in some popular fishing areas local authorities have placed restrictions on the amount of fishing in order to protect the turtles from being caught in fishing nets and drowning. However, the reduction in the amount of fishing in these areas has led to an increase in the numbers of the giant cuttlefish, which feed on the same underwater plants as the sea turtles do. The subsequent decrease in the turtles’ food source, particularly the sea grass that is part of the turtles’ staple diet, has not only led to an alarming reduction in the number of sea turtles in these areas but also affected the balance of the marine ecosystem in these regions.The passage is primarily concerned with

Detailed Solution for Test: Reading Comprehension: Bio Sciences - Question 13

Passage Analysis

 

Summary and Main Point

Pre-Thinking

This is a Main Idea question. The correct answer must be broad enough to encompass all of the paragraphs of the passage without veering outside the scope. Incorrect answer choices are often too narrow or focus only on one part of the passage.

The correct answer for this question should match the results of our passage analysis: the author establishes that sea turtles are vital to the planet’s ecosystem and states that human efforts to preserve the species are ironically endangering them even further.

Answer Choices

A

questioning certain human activities that are causing damage to not only the local fishing communities but also to a vital endangered species

Incorrect: Out of Scope

The passage does not really question these activities as much as it presents their effects, which are counter to what was expected. Also, there is no mention of any damage caused to the local fishing communities.

B

outlining the reasons behind the importance of a certain species to the Earth’s ecosystem

Incorrect: Partial Scope

This is the scope of only the first paragraph and not of the entire passage.

C

establishing the relevance of a species and analyzing how a solution to protect it might be defeating its very purpose

Correct

This choice matches the result of our passage analysis and our pre-thinking.

D

arguing that sometimes plans to rectify situations may actually cause more harm than good

Incorrect: Out of Scope

This choice is too broad in scope. The author does not argue for any such generalized opinion. The author does analyze one situation in which the results have been the opposite of what they were expected to be, but that’s not to make any broad statement. Also, this choice does not even mention the relevance of the species that forms the essence of the first paragraph.

E

explaining how some attempts to reduce fishing have not been successful

Incorrect: Inconsistent

The fact that there have been some attempts to reduce fishing is not the main point of the passage. Also, since the number of cuttlefish has increased, the attempts to reduce fishing in some areas were probably successful.

Test: Reading Comprehension: Bio Sciences - Question 14

Sea turtles, reptilian amphibians that are classified into seven distinct sub-species, are quickly beginning to rank among some of the most endangered species on the planet. These ancient reptiles are vital to Earth’s ecosystem because they feed on botanical life that grows on sea beds and thereby help maintain the natural habitat of several other marine life forms. Further, unhatched sea turtle eggs provide nutrients for plants that grow beneath the surface of the sea, which in turn strengthen sand dunes through their root systems and help prevent beaches from eroding.

Ironically, human attempts to preserve the marine environment in which sea turtles live are causing the species’ numbers to dwindle even faster. In an effort to protect sea turtles that nest on the beaches,  in some popular fishing areas local authorities have placed restrictions on the amount of fishing in order to protect the turtles from being caught in fishing nets and drowning. However, the reduction in the amount of fishing in these areas has led to an increase in the numbers of the giant cuttlefish, which feed on the same underwater plants as the sea turtles do. The subsequent decrease in the turtles’ food source, particularly the sea grass that is part of the turtles’ staple diet, has not only led to an alarming reduction in the number of sea turtles in these areas but also affected the balance of the marine ecosystem in these regions.

The author suggests which of the following about sea turtles?

Detailed Solution for Test: Reading Comprehension: Bio Sciences - Question 14

Passage Analysis

 

Summary and Main Point

Pre-Thinking

This is an Inference question. The correct answer will contain a statement that is implied by what is explicitly stated in the passage. Study each choice carefully and rule out the four that cannot be inferred from the passage.

Answer Choices

A

An increase in the number of sea turtles will probably lead to a decrease in the number of giant cuttlefish.

Incorrect: Out of Scope

No information is provided about the possible results of an increase in the number of ST. According to the passage, the number of GC has increased because of reduction in fishing. We do not know if GC would be affected by an increase in the number of ST.

B

Restrictions in the amount of fishing in some areas have led to an increase in illegal poaching of sea turtles.

Incorrect: Out of Scope

No information is provided to deduce anything about the poaching of sea turtles.

C

In some areas, sea turtles would probably be less endangered if giant cuttlefish populations were lower in number.

Correct

Since the passage states that increased giant cuttlefish (GC) numbers have led to a decrease in ST numbers, this choice can be inferred.

D

The plants that form part of the diet of sea turtles are found only on the sea bed.

Incorrect: Out of Scope

We cannot infer that these plants are found only on the sea bed.

E

Sea turtles are more endangered than turtle species that live on land.

Incorrect: Out of Scope

The passage does not make any comparison between ST and land turtles.

Test: Reading Comprehension: Bio Sciences - Question 15

Sea turtles, reptilian amphibians that are classified into seven distinct sub-species, are quickly beginning to rank among some of the most endangered species on the planet. These ancient reptiles are vital to Earth’s ecosystem because they feed on botanical life that grows on sea beds and thereby help maintain the natural habitat of several other marine life forms. Further, unhatched sea turtle eggs provide nutrients for plants that grow beneath the surface of the sea, which in turn strengthen sand dunes through their root systems and help prevent beaches from eroding.

Ironically, human attempts to preserve the marine environment in which sea turtles live are causing the species’ numbers to dwindle even faster. In an effort to protect sea turtles that nest on the beaches,  in some popular fishing areas local authorities have placed restrictions on the amount of fishing in order to protect the turtles from being caught in fishing nets and drowning. However, the reduction in the amount of fishing in these areas has led to an increase in the numbers of the giant cuttlefish, which feed on the same underwater plants as the sea turtles do. The subsequent decrease in the turtles’ food source, particularly the sea grass that is part of the turtles’ staple diet, has not only led to an alarming reduction in the number of sea turtles in these areas but also affected the balance of the marine ecosystem in these regions.Which of the following CANNOT be inferred from the passage?

Detailed Solution for Test: Reading Comprehension: Bio Sciences - Question 15

Passage Analysis

 

Summary and Main Point

 

Pre-Thinking

This is an Inference EXCEPT question. Four out of the five given answer choices will be based on information given in the passage. These choices are INCORRECT. Choose a choice that cannot be backed by any piece of information given in the passage.

Answer Choices

A

The habitat of some marine organisms is impacted by the existence of the sea-turtles.

Incorrect: Can be Inferred

The author states in the first paragraph that the sea turtles feed on botanical life that grows on sea beds and thereby help maintain the natural habitat of several other marine life forms. Hence, the information given in this choice can be inferred.

B

The staple diet of two marine organisms can be the same.

Correct: Out of Scope

The passage states that GC feeds on the same plants as ST and one of these plants forms the staple diet of ST. However, there is no given information tosuggest that this plant is also the staple diet of GC.

C

Even without feeding on plants, sea turtles can be useful to the environment they are born in.

Incorrect: Can be Inferred

This statement can be derived from the information given to us about the unhatched sea turtle eggs. These eggs, we are told, provide nutrients for certain plants that in turn prevent beaches from eroding.

D

Some attempts to help the endangered species of sea turtle have had effects that had not been predicted.

Incorrect: Can be Inferred

This statement can be inferred as we are told in the second paragraph that the efforts to help the species have caused harm instead. It is obvious that this effect was not a part of the plan.

E

The giant cuttlefish were being caught in greater numbers before certain restrictions on fishing were placed in some areas.

Incorrect: Can be Inferred

We are told that as result of the restrictions, the numbers of the GC increased. Therefore, we can conclude that before these restrictions, there were being caught in greater numbers.

Test: Reading Comprehension: Bio Sciences - Question 16

Sea turtles, reptilian amphibians that are classified into seven distinct sub-species, are quickly beginning to rank among some of the most endangered species on the planet. These ancient reptiles are vital to Earth’s ecosystem because they feed on botanical life that grows on sea beds and thereby help maintain the natural habitat of several other marine life forms. Further, unhatched sea turtle eggs provide nutrients for plants that grow beneath the surface of the sea, which in turn strengthen sand dunes through their root systems and help prevent beaches from eroding.

Ironically, human attempts to preserve the marine environment in which sea turtles live are causing the species’ numbers to dwindle even faster. In an effort to protect sea turtles that nest on the beaches,  in some popular fishing areas local authorities have placed restrictions on the amount of fishing in order to protect the turtles from being caught in fishing nets and drowning. However, the reduction in the amount of fishing in these areas has led to an increase in the numbers of the giant cuttlefish, which feed on the same underwater plants as the sea turtles do. The subsequent decrease in the turtles’ food source, particularly the sea grass that is part of the turtles’ staple diet, has not only led to an alarming reduction in the number of sea turtles in these areas but also affected the balance of the marine ecosystem in these regions.

The author refers to the giant cuttlefish in order to

Detailed Solution for Test: Reading Comprehension: Bio Sciences - Question 16

Passage Analysis

 

Summary and Main Point

 

Pre-Thinking

This is an Inference EXCEPT question. Four out of the five given answer choices will be based on information given in the passage. These choices are INCORRECT. Choose a choice that cannot be backed by any piece of information given in the passage.

Answer Choices

A

The habitat of some marine organisms is impacted by the existence of the sea-turtles.

Incorrect: Can be Inferred

The author states in the first paragraph that the sea turtles feed on botanical life that grows on sea beds and thereby help maintain the natural habitat of several other marine life forms. Hence, the information given in this choice can be inferred.

B

The staple diet of two marine organisms can be the same.

Correct: Out of Scope

The passage states that GC feeds on the same plants as ST and one of these plants forms the staple diet of ST. However, there is no given information tosuggest that this plant is also the staple diet of GC.

C

Even without feeding on plants, sea turtles can be useful to the environment they are born in.

Incorrect: Can be Inferred

This statement can be derived from the information given to us about the unhatched sea turtle eggs. These eggs, we are told, provide nutrients for certain plants that in turn prevent beaches from eroding.

D

Some attempts to help the endangered species of sea turtle have had effects that had not been predicted.

Incorrect: Can be Inferred

This statement can be inferred as we are told in the second paragraph that the efforts to help the species have caused harm instead. It is obvious that this effect was not a part of the plan.

E

The giant cuttlefish were being caught in greater numbers before certain restrictions on fishing were placed in some areas.

Incorrect: Can be Inferred

We are told that as result of the restrictions, the numbers of the GC increased. Therefore, we can conclude that before these restrictions, there were being caught in greater numbers.

Test: Reading Comprehension: Bio Sciences - Question 17

This much was well known that the purpose of a gene is to store the recipe for making proteins and that we inherit from our parents a gigantic list of recipes for making proteins and protein-making machines.  What was not clear as late as the early 20th century until Gregor Mendel’s experiments were published and understood was that when crossed, the expression of these genes skipped a generation.

Mendel discovered that when white flower and purple flower plants are crossed, the result is not a blend. Rather than being a mix of the two, the offspring was purple flowered. He then conceived the idea of heredity units, which he called "factors", one of which is a recessive characteristic and the other dominant. Mendel said that factors, later called genes, normally occur in pairs in ordinary body cells, yet segregate during the formation of sex cells. The dominant gene, such as the purple flower in Mendel's plants, will hide the recessive gene, the white flower. Mendel crossed over 29,000 plants including inflated seed pods with wrinkled seed pods, green unripe pods with yellow unripe pods, and axial flowers with terminal flowers. In every case the resulting hybrids were just like one parent with the essence of other parent missing. However, as these hybrids were allowed to self-fertilize, the essence of the recessed parent re-appeared in exactly one third of the cases. This re-appearance is called the law of thirds. This law is not just obeyed in plants but also in every living species as demonstrated by Nageli’s experiment on crossing angora cats with another breed. Nageli observed that the angora coat disappeared in the next generation but re-appeared in the kittens in the third. 

Mendel’s law has been put to a variety of uses such as selecting the right plants to hybridize to get the desired mix of dominant factors. A surprising use of the law has been to explain Alkaptonuria in which the patients suffered from arthritis and their urine and the ear wax turned reddish black upon exposure to air. Rare in the general population but frequent in children of first-cousin marriages, the incidence of Alkaptonuria is attributed to expression of recessive factors.

According to the passage, all of the following about Mendel’s dominant factors are true except 

Detailed Solution for Test: Reading Comprehension: Bio Sciences - Question 17

The passage states that Mendel's dominant factors, which were later called genes, normally occur in pairs in ordinary body cells and segregate during the formation of sex cells. These factors define some of the key characteristics of the first offspring when crossed. However, the passage does not mention that these dominant factors are responsible for the incidence of Alkaptonuria. It states that Alkaptonuria is attributed to the expression of recessive factors.

Test: Reading Comprehension: Bio Sciences - Question 18

This much was well known that the purpose of a gene is to store the recipe for making proteins and that we inherit from our parents a gigantic list of recipes for making proteins and protein-making machines.  What was not clear as late as the early 20th century until Gregor Mendel’s experiments were published and understood was that when crossed, the expression of these genes skipped a generation.

Mendel discovered that when white flower and purple flower plants are crossed, the result is not a blend. Rather than being a mix of the two, the offspring was purple flowered. He then conceived the idea of heredity units, which he called "factors", one of which is a recessive characteristic and the other dominant. Mendel said that factors, later called genes, normally occur in pairs in ordinary body cells, yet segregate during the formation of sex cells. The dominant gene, such as the purple flower in Mendel's plants, will hide the recessive gene, the white flower. Mendel crossed over 29,000 plants including inflated seed pods with wrinkled seed pods, green unripe pods with yellow unripe pods, and axial flowers with terminal flowers. In every case the resulting hybrids were just like one parent with the essence of other parent missing. However, as these hybrids were allowed to self-fertilize, the essence of the recessed parent re-appeared in exactly one third of the cases. This re-appearance is called the law of thirds. This law is not just obeyed in plants but also in every living species as demonstrated by Nageli’s experiment on crossing angora cats with another breed. Nageli observed that the angora coat disappeared in the next generation but re-appeared in the kittens in the third. 

Mendel’s law has been put to a variety of uses such as selecting the right plants to hybridize to get the desired mix of dominant factors. A surprising use of the law has been to explain Alkaptonuria in which the patients suffered from arthritis and their urine and the ear wax turned reddish black upon exposure to air. Rare in the general population but frequent in children of first-cousin marriages, the incidence of Alkaptonuria is attributed to expression of recessive factors.

The author mentions Nageli’s experiment to illustrate 

Detailed Solution for Test: Reading Comprehension: Bio Sciences - Question 18

Answer Choices

A

How unique property of the Angora cat – its fur can be transferred to another cat species.

This choice states the result of the experiment but not the purpose

B

An example of the validity of law of thirds in other living organisms.

Reword of the purpose of entity as derived in question analysis.

C

That it is possible to cross fertilize extremely distinct species. 

Proof of cross fertilizing extremely distinct species is outside the scope of the passage.

D

An instance in which the recessive factor dominates the first offspring.

The fact stated in this choice is opposite to what is stated in the passage.

E

Demonstrate how selective species when cross hybridized could lead to an offspring with extremely desirable characteristics.

While this fact is true, it is not the purpose of why Nageli’s experiment is mentioned in the passage.

Test: Reading Comprehension: Bio Sciences - Question 19

This much was well known that the purpose of a gene is to store the recipe for making proteins and that we inherit from our parents a gigantic list of recipes for making proteins and protein-making machines.  What was not clear as late as the early 20th century until Gregor Mendel’s experiments were published and understood was that when crossed, the expression of these genes skipped a generation.

Mendel discovered that when white flower and purple flower plants are crossed, the result is not a blend. Rather than being a mix of the two, the offspring was purple flowered. He then conceived the idea of heredity units, which he called "factors", one of which is a recessive characteristic and the other dominant. Mendel said that factors, later called genes, normally occur in pairs in ordinary body cells, yet segregate during the formation of sex cells. The dominant gene, such as the purple flower in Mendel's plants, will hide the recessive gene, the white flower. Mendel crossed over 29,000 plants including inflated seed pods with wrinkled seed pods, green unripe pods with yellow unripe pods, and axial flowers with terminal flowers. In every case the resulting hybrids were just like one parent with the essence of other parent missing. However, as these hybrids were allowed to self-fertilize, the essence of the recessed parent re-appeared in exactly one third of the cases. This re-appearance is called the law of thirds. This law is not just obeyed in plants but also in every living species as demonstrated by Nageli’s experiment on crossing angora cats with another breed. Nageli observed that the angora coat disappeared in the next generation but re-appeared in the kittens in the third. 

Mendel’s law has been put to a variety of uses such as selecting the right plants to hybridize to get the desired mix of dominant factors. A surprising use of the law has been to explain Alkaptonuria in which the patients suffered from arthritis and their urine and the ear wax turned reddish black upon exposure to air. Rare in the general population but frequent in children of first-cousin marriages, the incidence of Alkaptonuria is attributed to expression of recessive factors.

The primary purpose of the passage is to 

 

Detailed Solution for Test: Reading Comprehension: Bio Sciences - Question 19

Answer Choices

A

Explain Mendel's laws and its utilities

Correct answer as discussed.

B

Describe why a phenomena that was readily observed took so long to be formalized

No such discussion in the passage

C

Illustrate how Mendel discovered the law of thirds.

D

Presented only in second paragraph of the 3 paragraph passage.

Show with appropriate examples, that cross breeding can lead to  offsprings that may show characteristics that are present in neither of the parents.

Not discussed in the passage.

E

To evaluate some of the benefits of Mendal’s law of thirds

Presented only in third paragraph of the 3 paragraph passage.

Test: Reading Comprehension: Bio Sciences - Question 20

This much was well known that the purpose of a gene is to store the recipe for making proteins and that we inherit from our parents a gigantic list of recipes for making proteins and protein-making machines.  What was not clear as late as the early 20th century until Gregor Mendel’s experiments were published and understood was that when crossed, the expression of these genes skipped a generation.

Mendel discovered that when white flower and purple flower plants are crossed, the result is not a blend. Rather than being a mix of the two, the offspring was purple flowered. He then conceived the idea of heredity units, which he called "factors", one of which is a recessive characteristic and the other dominant. Mendel said that factors, later called genes, normally occur in pairs in ordinary body cells, yet segregate during the formation of sex cells. The dominant gene, such as the purple flower in Mendel's plants, will hide the recessive gene, the white flower. Mendel crossed over 29,000 plants including inflated seed pods with wrinkled seed pods, green unripe pods with yellow unripe pods, and axial flowers with terminal flowers. In every case the resulting hybrids were just like one parent with the essence of other parent missing. However, as these hybrids were allowed to self-fertilize, the essence of the recessed parent re-appeared in exactly one third of the cases. This re-appearance is called the law of thirds. This law is not just obeyed in plants but also in every living species as demonstrated by Nageli’s experiment on crossing angora cats with another breed. Nageli observed that the angora coat disappeared in the next generation but re-appeared in the kittens in the third. 

Mendel’s law has been put to a variety of uses such as selecting the right plants to hybridize to get the desired mix of dominant factors. A surprising use of the law has been to explain Alkaptonuria in which the patients suffered from arthritis and their urine and the ear wax turned reddish black upon exposure to air. Rare in the general population but frequent in children of first-cousin marriages, the incidence of Alkaptonuria is attributed to expression of recessive factors.

According to the passage, which of the following is not true about genes?

Detailed Solution for Test: Reading Comprehension: Bio Sciences - Question 20

Answer Choices

A

Genes store a recipe for making proteins.

Per Passage “the purpose of a gene is to store the recipe for making proteins”

B

We inherit a number of genes from our parents.

  • Per Passage “that we inherit from our parents a gigantic list of recipes”.
  • Recipe is stored in genes, so we inherit genes from our parents.

C

They occur in pairs in every cell but those that govern our sex.

  • Per Passage “factors, later called genes, normally occur in pairs in ordinary body cells, yet segregate during the formation of sex cells.”

D

The dominant genes in crossed offspring may never allow the recessive gene to express even in a future generations.

The law of thirds explained in the pasasge states opposite to this choice.  So this choice is NOT TRUE about genes.

E

The recessive gene in a crossed offspring is not expressed in the first generation.

  • Per Passage “The dominant gene, such as the purple flower in Mendel's plants, will hide the recessive gene, the white flower”.
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