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Consider the following statements:
Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.
Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.
Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.
Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.
- a)Both A and R are true and R is the correct explanation of A.
- b)Both A and R are true, but R is not the correct explanation of A.
- c)A is true, but R is false.
- d)A is false, but R is true.
Correct answer is option 'A'. Can you explain this answer?
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Consider the following statements:Assertion (A): Scientists can cut ap...
In genetic engineering, a DNA segment from any foreign source can be inserted into any other genetic material. The enzymes, called restriction endonucleases, act like scissors that cut apart a particular or specific part of the DNA. This cut out DNA piece can be inserted into other genetic material which has been cut to make space for containing the foreign DNA. The DNA once inserted can be ligated by enzymes known as ligases.
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Consider the following statements:Assertion (A): Scientists can cut ap...
Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.
Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.
The correct answer is option 'A', which means both the assertion and the reason are true, and the reason is the correct explanation of the assertion.
Explanation:
DNA manipulation is a fundamental technique in molecular biology that allows scientists to study and modify genetic material. It involves cutting DNA molecules at specific locations and then recombining them in desired ways.
Restriction Endonucleases:
Restriction endonucleases, also known as restriction enzymes, are enzymes that can recognize specific DNA sequences and cut the DNA molecules at these sites. These enzymes are derived from bacteria and are part of their defense mechanism against foreign DNA, such as viral DNA.
- Restriction endonucleases: These enzymes recognize specific DNA sequences, known as restriction sites, and cleave the DNA at or near these sites.
- Cutting DNA: By using restriction endonucleases, scientists can cut DNA molecules at specific locations, resulting in DNA fragments with defined ends.
- Sticky ends: The cuts made by restriction endonucleases often result in "sticky ends," where the DNA fragments have short single-stranded overhangs that can base pair with complementary sequences.
DNA Ligases:
DNA ligases are enzymes that can join DNA fragments together by catalyzing the formation of phosphodiester bonds between the ends of the fragments.
- Joining DNA fragments: DNA ligases can be used to join DNA fragments with complementary sticky ends. The enzyme catalyzes the formation of phosphodiester bonds between the sugar-phosphate backbones of the DNA fragments, creating a continuous DNA molecule.
- Sealing nicks: DNA ligases can also seal nicks in the DNA backbone, resulting in a continuous DNA molecule.
Manipulating DNA:
By utilizing restriction endonucleases and DNA ligases, scientists can manipulate DNA molecules in various ways:
- Inserting foreign DNA: DNA fragments from different sources can be cut with the same restriction enzyme, resulting in complementary sticky ends. These fragments can then be joined together using DNA ligase, allowing the insertion of foreign DNA into a target DNA molecule.
- Deleting DNA: DNA fragments can be selectively removed by cutting the target DNA molecule with a restriction enzyme and then ligating the ends, excluding the unwanted fragment.
- Modifying DNA: DNA molecules can be modified by introducing specific changes in the DNA sequence. This can be achieved by cutting the DNA at specific locations, removing or replacing specific fragments, and then rejoining the DNA using DNA ligase.
In conclusion, scientists can indeed cut apart and paste together DNA molecules at will, regardless of the source of the molecules, by utilizing the techniques of restriction endonucleases and DNA ligases. These enzymes allow for precise manipulation of DNA fragments, enabling various genetic engineering applications and molecular biology research.
Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.
The correct answer is option 'A', which means both the assertion and the reason are true, and the reason is the correct explanation of the assertion.
Explanation:
DNA manipulation is a fundamental technique in molecular biology that allows scientists to study and modify genetic material. It involves cutting DNA molecules at specific locations and then recombining them in desired ways.
Restriction Endonucleases:
Restriction endonucleases, also known as restriction enzymes, are enzymes that can recognize specific DNA sequences and cut the DNA molecules at these sites. These enzymes are derived from bacteria and are part of their defense mechanism against foreign DNA, such as viral DNA.
- Restriction endonucleases: These enzymes recognize specific DNA sequences, known as restriction sites, and cleave the DNA at or near these sites.
- Cutting DNA: By using restriction endonucleases, scientists can cut DNA molecules at specific locations, resulting in DNA fragments with defined ends.
- Sticky ends: The cuts made by restriction endonucleases often result in "sticky ends," where the DNA fragments have short single-stranded overhangs that can base pair with complementary sequences.
DNA Ligases:
DNA ligases are enzymes that can join DNA fragments together by catalyzing the formation of phosphodiester bonds between the ends of the fragments.
- Joining DNA fragments: DNA ligases can be used to join DNA fragments with complementary sticky ends. The enzyme catalyzes the formation of phosphodiester bonds between the sugar-phosphate backbones of the DNA fragments, creating a continuous DNA molecule.
- Sealing nicks: DNA ligases can also seal nicks in the DNA backbone, resulting in a continuous DNA molecule.
Manipulating DNA:
By utilizing restriction endonucleases and DNA ligases, scientists can manipulate DNA molecules in various ways:
- Inserting foreign DNA: DNA fragments from different sources can be cut with the same restriction enzyme, resulting in complementary sticky ends. These fragments can then be joined together using DNA ligase, allowing the insertion of foreign DNA into a target DNA molecule.
- Deleting DNA: DNA fragments can be selectively removed by cutting the target DNA molecule with a restriction enzyme and then ligating the ends, excluding the unwanted fragment.
- Modifying DNA: DNA molecules can be modified by introducing specific changes in the DNA sequence. This can be achieved by cutting the DNA at specific locations, removing or replacing specific fragments, and then rejoining the DNA using DNA ligase.
In conclusion, scientists can indeed cut apart and paste together DNA molecules at will, regardless of the source of the molecules, by utilizing the techniques of restriction endonucleases and DNA ligases. These enzymes allow for precise manipulation of DNA fragments, enabling various genetic engineering applications and molecular biology research.
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Consider the following statements:Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.a)Both A and R are true and R is the correct explanation of A.b)Both A and R are true, but R is not the correct explanation of A.c)A is true, but R is false.d)A is false, but R is true.Correct answer is option 'A'. Can you explain this answer?
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Consider the following statements:Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.a)Both A and R are true and R is the correct explanation of A.b)Both A and R are true, but R is not the correct explanation of A.c)A is true, but R is false.d)A is false, but R is true.Correct answer is option 'A'. Can you explain this answer? for UPSC 2025 is part of UPSC preparation. The Question and answers have been prepared according to the UPSC exam syllabus. Information about Consider the following statements:Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.a)Both A and R are true and R is the correct explanation of A.b)Both A and R are true, but R is not the correct explanation of A.c)A is true, but R is false.d)A is false, but R is true.Correct answer is option 'A'. Can you explain this answer? covers all topics & solutions for UPSC 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Consider the following statements:Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.a)Both A and R are true and R is the correct explanation of A.b)Both A and R are true, but R is not the correct explanation of A.c)A is true, but R is false.d)A is false, but R is true.Correct answer is option 'A'. Can you explain this answer?.
Consider the following statements:Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.a)Both A and R are true and R is the correct explanation of A.b)Both A and R are true, but R is not the correct explanation of A.c)A is true, but R is false.d)A is false, but R is true.Correct answer is option 'A'. Can you explain this answer? for UPSC 2025 is part of UPSC preparation. The Question and answers have been prepared according to the UPSC exam syllabus. Information about Consider the following statements:Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.a)Both A and R are true and R is the correct explanation of A.b)Both A and R are true, but R is not the correct explanation of A.c)A is true, but R is false.d)A is false, but R is true.Correct answer is option 'A'. Can you explain this answer? covers all topics & solutions for UPSC 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Consider the following statements:Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.a)Both A and R are true and R is the correct explanation of A.b)Both A and R are true, but R is not the correct explanation of A.c)A is true, but R is false.d)A is false, but R is true.Correct answer is option 'A'. Can you explain this answer?.
Solutions for Consider the following statements:Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.a)Both A and R are true and R is the correct explanation of A.b)Both A and R are true, but R is not the correct explanation of A.c)A is true, but R is false.d)A is false, but R is true.Correct answer is option 'A'. Can you explain this answer? in English & in Hindi are available as part of our courses for UPSC.
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Consider the following statements:Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.a)Both A and R are true and R is the correct explanation of A.b)Both A and R are true, but R is not the correct explanation of A.c)A is true, but R is false.d)A is false, but R is true.Correct answer is option 'A'. Can you explain this answer?, a detailed solution for Consider the following statements:Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.a)Both A and R are true and R is the correct explanation of A.b)Both A and R are true, but R is not the correct explanation of A.c)A is true, but R is false.d)A is false, but R is true.Correct answer is option 'A'. Can you explain this answer? has been provided alongside types of Consider the following statements:Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.a)Both A and R are true and R is the correct explanation of A.b)Both A and R are true, but R is not the correct explanation of A.c)A is true, but R is false.d)A is false, but R is true.Correct answer is option 'A'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice Consider the following statements:Assertion (A): Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.Reason (R): DNA fragments can be manipulated from restriction endonucleases and DNA ligases.a)Both A and R are true and R is the correct explanation of A.b)Both A and R are true, but R is not the correct explanation of A.c)A is true, but R is false.d)A is false, but R is true.Correct answer is option 'A'. Can you explain this answer? tests, examples and also practice UPSC tests.
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