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In a bacteria possessing the lac operon, which of the following occurs when glucose is low and lactose is abundant?
- a)Beta-galactosidase acetylases the operon
- b)Lactose permease cleaves lactose to glucose and galactose
- c)Lactose metabolism is increased by lactose binding to the operon
- d)Transport of lactose into the cell is enhanced
Correct answer is option 'D'. Can you explain this answer?
Verified Answer
In a bacteria possessing the lac operon, which of the following occurs...
In a bacterium possessing the lac operon, when glucose is low and lactose is abundant, the lac operon is induced to allow the transport and metabolism of lactose. In this condition, the lac repressor protein is not bound to the operator region of the operon, and as a result, the lacZ and lacY genes are transcribed.
The lacY gene encodes for lactose permease, a transporter protein that facilitates the uptake of lactose into the bacterial cell. When lactose is abundant, the presence of lactose molecules induces the expression of the lacY gene and increases the production of lactose permease. This enhances the transport of lactose into the cell, enabling the bacterium to utilize lactose as an energy source in the absence of glucose.
Therefore, option D is the correct answer as it describes the enhanced transport of lactose into the bacterial cell in the presence of low glucose and abundant lactose.
Most Upvoted Answer
In a bacteria possessing the lac operon, which of the following occurs...
Transport of lactose into the cell is enhanced
When glucose levels are low and lactose is abundant in a bacterium with the lac operon, the following events occur:
- Induction of the lac operon: The lac operon is activated in response to low glucose levels and the presence of lactose. This leads to the expression of genes involved in lactose metabolism.
- Lactose binds to the repressor: In the absence of glucose and the presence of lactose, lactose binds to the lac repressor protein. This causes a conformational change in the repressor, preventing it from binding to the operator region of the lac operon.
- Enhanced transport of lactose: Lactose permease, a membrane protein encoded by the lac operon, is responsible for transporting lactose into the cell. When the lac operon is induced, more lactose permease is produced, leading to an increase in the transport of lactose into the bacterial cell.
- Lactose metabolism: Once inside the cell, lactose is cleaved by the enzyme beta-galactosidase into glucose and galactose. This allows the bacterium to utilize lactose as a carbon source in the absence of glucose.
Therefore, when glucose is low and lactose is abundant, the lac operon is activated, leading to enhanced transport of lactose into the cell, ultimately allowing the bacterium to metabolize lactose for energy production.
When glucose levels are low and lactose is abundant in a bacterium with the lac operon, the following events occur:
- Induction of the lac operon: The lac operon is activated in response to low glucose levels and the presence of lactose. This leads to the expression of genes involved in lactose metabolism.
- Lactose binds to the repressor: In the absence of glucose and the presence of lactose, lactose binds to the lac repressor protein. This causes a conformational change in the repressor, preventing it from binding to the operator region of the lac operon.
- Enhanced transport of lactose: Lactose permease, a membrane protein encoded by the lac operon, is responsible for transporting lactose into the cell. When the lac operon is induced, more lactose permease is produced, leading to an increase in the transport of lactose into the bacterial cell.
- Lactose metabolism: Once inside the cell, lactose is cleaved by the enzyme beta-galactosidase into glucose and galactose. This allows the bacterium to utilize lactose as a carbon source in the absence of glucose.
Therefore, when glucose is low and lactose is abundant, the lac operon is activated, leading to enhanced transport of lactose into the cell, ultimately allowing the bacterium to metabolize lactose for energy production.
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In a bacteria possessing the lac operon, which of the following occurs when glucose is low and lactose is abundant?a)Beta-galactosidase acetylases the operonb)Lactose permease cleaves lactose to glucose and galactosec)Lactose metabolism is increased by lactose binding to the operond)Transport of lactose into the cell is enhancedCorrect answer is option 'D'. Can you explain this answer? for MCAT 2025 is part of MCAT preparation. The Question and answers have been prepared according to the MCAT exam syllabus. Information about In a bacteria possessing the lac operon, which of the following occurs when glucose is low and lactose is abundant?a)Beta-galactosidase acetylases the operonb)Lactose permease cleaves lactose to glucose and galactosec)Lactose metabolism is increased by lactose binding to the operond)Transport of lactose into the cell is enhancedCorrect answer is option 'D'. Can you explain this answer? covers all topics & solutions for MCAT 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for In a bacteria possessing the lac operon, which of the following occurs when glucose is low and lactose is abundant?a)Beta-galactosidase acetylases the operonb)Lactose permease cleaves lactose to glucose and galactosec)Lactose metabolism is increased by lactose binding to the operond)Transport of lactose into the cell is enhancedCorrect answer is option 'D'. Can you explain this answer?.
In a bacteria possessing the lac operon, which of the following occurs when glucose is low and lactose is abundant?a)Beta-galactosidase acetylases the operonb)Lactose permease cleaves lactose to glucose and galactosec)Lactose metabolism is increased by lactose binding to the operond)Transport of lactose into the cell is enhancedCorrect answer is option 'D'. Can you explain this answer? for MCAT 2025 is part of MCAT preparation. The Question and answers have been prepared according to the MCAT exam syllabus. Information about In a bacteria possessing the lac operon, which of the following occurs when glucose is low and lactose is abundant?a)Beta-galactosidase acetylases the operonb)Lactose permease cleaves lactose to glucose and galactosec)Lactose metabolism is increased by lactose binding to the operond)Transport of lactose into the cell is enhancedCorrect answer is option 'D'. Can you explain this answer? covers all topics & solutions for MCAT 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for In a bacteria possessing the lac operon, which of the following occurs when glucose is low and lactose is abundant?a)Beta-galactosidase acetylases the operonb)Lactose permease cleaves lactose to glucose and galactosec)Lactose metabolism is increased by lactose binding to the operond)Transport of lactose into the cell is enhancedCorrect answer is option 'D'. Can you explain this answer?.
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In a bacteria possessing the lac operon, which of the following occurs when glucose is low and lactose is abundant?a)Beta-galactosidase acetylases the operonb)Lactose permease cleaves lactose to glucose and galactosec)Lactose metabolism is increased by lactose binding to the operond)Transport of lactose into the cell is enhancedCorrect answer is option 'D'. Can you explain this answer?, a detailed solution for In a bacteria possessing the lac operon, which of the following occurs when glucose is low and lactose is abundant?a)Beta-galactosidase acetylases the operonb)Lactose permease cleaves lactose to glucose and galactosec)Lactose metabolism is increased by lactose binding to the operond)Transport of lactose into the cell is enhancedCorrect answer is option 'D'. Can you explain this answer? has been provided alongside types of In a bacteria possessing the lac operon, which of the following occurs when glucose is low and lactose is abundant?a)Beta-galactosidase acetylases the operonb)Lactose permease cleaves lactose to glucose and galactosec)Lactose metabolism is increased by lactose binding to the operond)Transport of lactose into the cell is enhancedCorrect answer is option 'D'. Can you explain this answer? theory, EduRev gives you an
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