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Case-I
To answer the questions, study the paragraph given below:
The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.
The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.
Q.When the process of Lac operon is blocked by a repressor it represents:
- a)Positive regulation
- b)Negative regulation
- c)sometimes positive sometimes negative
- d)both positive and negative regulation
Correct answer is option 'B'. Can you explain this answer?
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Case-ITo answer the questions, study the paragraph given below:The lac...
The lac operon regulation can be in both negative and positive ways. It is a negative control system because expression is typically blocked by an active repressor (the lac repressor) that turns off transcription and when CAP (catabolite gene activating protein) binds upstream of this operator region near the promoter and transcription increases, this is an example of a positive system.
Most Upvoted Answer
Case-ITo answer the questions, study the paragraph given below:The lac...
Explanation:
When the process of Lac operon is blocked by a repressor, it represents negative regulation. Let's break down the given paragraph to understand why.
Lac Operon:
- The lac operon is a segment of DNA in bacteria that contains genes for the metabolism of lactose.
- It consists of a regulation gene and three structural genes.
Role of Repressor:
- The repressor is a protein encoded by the regulation gene of the lac operon.
- Its primary function is to regulate the expression of the structural genes by binding to the operator region of the operon.
- When the repressor binds to the operator, it prevents RNA polymerase from transcribing the operon.
Inducer and Repressor Interaction:
- The lac operon is inducible, which means it is usually turned off and needs to be activated when lactose is present.
- In the presence of an inducer such as lactose, the repressor is inactivated during the interaction.
- When lactose binds to the repressor, it undergoes a conformational change and cannot bind to the operator.
- As a result, RNA polymerase gains access to the promoter region, and transcription of the structural genes can proceed.
Summary:
- When the repressor is active and binds to the operator, it blocks the transcription of the lac operon.
- This mechanism represents negative regulation because it inhibits gene expression.
- In the absence of lactose, the lac operon remains repressed, and the repressor prevents RNA polymerase from transcribing the genes.
- However, in the presence of lactose, the inducer binds to the repressor, inactivates it, and allows transcription to occur.
Conclusion:
Hence, the correct answer is option B) Negative regulation.
When the process of Lac operon is blocked by a repressor, it represents negative regulation. Let's break down the given paragraph to understand why.
Lac Operon:
- The lac operon is a segment of DNA in bacteria that contains genes for the metabolism of lactose.
- It consists of a regulation gene and three structural genes.
Role of Repressor:
- The repressor is a protein encoded by the regulation gene of the lac operon.
- Its primary function is to regulate the expression of the structural genes by binding to the operator region of the operon.
- When the repressor binds to the operator, it prevents RNA polymerase from transcribing the operon.
Inducer and Repressor Interaction:
- The lac operon is inducible, which means it is usually turned off and needs to be activated when lactose is present.
- In the presence of an inducer such as lactose, the repressor is inactivated during the interaction.
- When lactose binds to the repressor, it undergoes a conformational change and cannot bind to the operator.
- As a result, RNA polymerase gains access to the promoter region, and transcription of the structural genes can proceed.
Summary:
- When the repressor is active and binds to the operator, it blocks the transcription of the lac operon.
- This mechanism represents negative regulation because it inhibits gene expression.
- In the absence of lactose, the lac operon remains repressed, and the repressor prevents RNA polymerase from transcribing the genes.
- However, in the presence of lactose, the inducer binds to the repressor, inactivates it, and allows transcription to occur.
Conclusion:
Hence, the correct answer is option B) Negative regulation.
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Case-ITo answer the questions, study the paragraph given below:The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.Q.When the process of Lac operon is blocked by a repressor it represents:a)Positive regulation b)Negative regulation c)sometimes positive sometimes negative d)both positive and negative regulationCorrect answer is option 'B'. Can you explain this answer?
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Case-ITo answer the questions, study the paragraph given below:The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.Q.When the process of Lac operon is blocked by a repressor it represents:a)Positive regulation b)Negative regulation c)sometimes positive sometimes negative d)both positive and negative regulationCorrect answer is option 'B'. Can you explain this answer? for Class 12 2024 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about Case-ITo answer the questions, study the paragraph given below:The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.Q.When the process of Lac operon is blocked by a repressor it represents:a)Positive regulation b)Negative regulation c)sometimes positive sometimes negative d)both positive and negative regulationCorrect answer is option 'B'. Can you explain this answer? covers all topics & solutions for Class 12 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Case-ITo answer the questions, study the paragraph given below:The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.Q.When the process of Lac operon is blocked by a repressor it represents:a)Positive regulation b)Negative regulation c)sometimes positive sometimes negative d)both positive and negative regulationCorrect answer is option 'B'. Can you explain this answer?.
Case-ITo answer the questions, study the paragraph given below:The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.Q.When the process of Lac operon is blocked by a repressor it represents:a)Positive regulation b)Negative regulation c)sometimes positive sometimes negative d)both positive and negative regulationCorrect answer is option 'B'. Can you explain this answer? for Class 12 2024 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about Case-ITo answer the questions, study the paragraph given below:The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.Q.When the process of Lac operon is blocked by a repressor it represents:a)Positive regulation b)Negative regulation c)sometimes positive sometimes negative d)both positive and negative regulationCorrect answer is option 'B'. Can you explain this answer? covers all topics & solutions for Class 12 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Case-ITo answer the questions, study the paragraph given below:The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.Q.When the process of Lac operon is blocked by a repressor it represents:a)Positive regulation b)Negative regulation c)sometimes positive sometimes negative d)both positive and negative regulationCorrect answer is option 'B'. Can you explain this answer?.
Solutions for Case-ITo answer the questions, study the paragraph given below:The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.Q.When the process of Lac operon is blocked by a repressor it represents:a)Positive regulation b)Negative regulation c)sometimes positive sometimes negative d)both positive and negative regulationCorrect answer is option 'B'. Can you explain this answer? in English & in Hindi are available as part of our courses for Class 12.
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Here you can find the meaning of Case-ITo answer the questions, study the paragraph given below:The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.Q.When the process of Lac operon is blocked by a repressor it represents:a)Positive regulation b)Negative regulation c)sometimes positive sometimes negative d)both positive and negative regulationCorrect answer is option 'B'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
Case-ITo answer the questions, study the paragraph given below:The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.Q.When the process of Lac operon is blocked by a repressor it represents:a)Positive regulation b)Negative regulation c)sometimes positive sometimes negative d)both positive and negative regulationCorrect answer is option 'B'. Can you explain this answer?, a detailed solution for Case-ITo answer the questions, study the paragraph given below:The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.Q.When the process of Lac operon is blocked by a repressor it represents:a)Positive regulation b)Negative regulation c)sometimes positive sometimes negative d)both positive and negative regulationCorrect answer is option 'B'. Can you explain this answer? has been provided alongside types of Case-ITo answer the questions, study the paragraph given below:The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.Q.When the process of Lac operon is blocked by a repressor it represents:a)Positive regulation b)Negative regulation c)sometimes positive sometimes negative d)both positive and negative regulationCorrect answer is option 'B'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice Case-ITo answer the questions, study the paragraph given below:The lac operon consists of a regulation gene and three structural gene. The lactose acts as inducer. In the presence of an Inducer such as lactose, the repressor is in inactivated during the interaction. This allows RNA polymerase access to the promoter and transcription proceeds. The repressor is synthesized which in turn binds with the operator region of the operon and prevents RNA polymerase from transcribing the operon.Q.When the process of Lac operon is blocked by a repressor it represents:a)Positive regulation b)Negative regulation c)sometimes positive sometimes negative d)both positive and negative regulationCorrect answer is option 'B'. Can you explain this answer? tests, examples and also practice Class 12 tests.
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