IIT JAM Exam  >  IIT JAM Questions  >  Which of the following events occur when E. c... Start Learning for Free
Which of the following events occur when E. coli is straved for tryptophan ?
  • a)
    The ribosome translates the leader peptide completely
  • b)
    Transcription reads through attenuator into trp EDCBA
  • c)
    Tryptophanyl tRNA is not formed
  • d)
    A stem loop structure involving regions 3 and 4 is formed at attenuator site.
Correct answer is option 'B,C'. Can you explain this answer?
Verified Answer
Which of the following events occur when E. coli is straved for trypto...
In the absence of tryptophan, the ribosomes would stall at trp codons in the leader sequence present in region1. This allows region 2 and 3 to pair and from an anti-termination loop, which allows transcription to continue into trp EDCBA genes, which code the enzymes for tryptophan synthesis. Since tryptophan is not present, so tryptophanyl- tRNA would not be formed, hence options b and c are  correct.
View all questions of this test
Most Upvoted Answer
Which of the following events occur when E. coli is straved for trypto...
When E. coli is starved for tryptophan, several events occur as a response to the depletion of this essential amino acid. The correct options are B and C, which are explained in detail below:

b) Transcription reads through attenuator into trp EDCBA:
In the absence of tryptophan, the ribosome translating the leader peptide completes the translation. This leads to the formation of the amino acid sequence called the leader peptide. The leader peptide contains a region called the attenuator. The attenuator is a regulatory sequence located upstream of the trp operon, which is responsible for the production of tryptophan.

The attenuator sequence has four regions, numbered 1 to 4. When tryptophan levels are low, the ribosome translating the leader peptide stalls at the tryptophan codons in region 1. This stalling prevents the formation of a stem loop structure involving regions 2 and 3 of the attenuator. As a result, the RNA polymerase continues transcription and reads through the attenuator into the trp operon, allowing the synthesis of enzymes involved in tryptophan biosynthesis.

c) Tryptophanyl tRNA is not formed:
In the absence of tryptophan, the trp operon is derepressed, and the synthesis of tryptophan enzymes is initiated. However, tryptophan biosynthesis cannot proceed without the presence of tryptophanyl tRNA. Tryptophanyl tRNA is responsible for carrying the amino acid tryptophan to the ribosome during protein synthesis. When tryptophan levels are low, the tryptophanyl tRNA is not formed, leading to a decrease in protein synthesis.

Therefore, when E. coli is starved for tryptophan, the transcription reads through the attenuator into the trp operon, allowing the synthesis of tryptophan enzymes. However, the absence of tryptophanyl tRNA prevents the biosynthesis of tryptophan and reduces protein synthesis.
Explore Courses for IIT JAM exam
Which of the following events occur when E. coli is straved for tryptophan ?a)The ribosome translates the leader peptide completelyb)Transcription reads through attenuator into trp EDCBAc)Tryptophanyl tRNA is not formedd)A stem loop structure involving regions 3 and 4 is formed at attenuator site.Correct answer is option 'B,C'. Can you explain this answer?
Question Description
Which of the following events occur when E. coli is straved for tryptophan ?a)The ribosome translates the leader peptide completelyb)Transcription reads through attenuator into trp EDCBAc)Tryptophanyl tRNA is not formedd)A stem loop structure involving regions 3 and 4 is formed at attenuator site.Correct answer is option 'B,C'. Can you explain this answer? for IIT JAM 2024 is part of IIT JAM preparation. The Question and answers have been prepared according to the IIT JAM exam syllabus. Information about Which of the following events occur when E. coli is straved for tryptophan ?a)The ribosome translates the leader peptide completelyb)Transcription reads through attenuator into trp EDCBAc)Tryptophanyl tRNA is not formedd)A stem loop structure involving regions 3 and 4 is formed at attenuator site.Correct answer is option 'B,C'. Can you explain this answer? covers all topics & solutions for IIT JAM 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Which of the following events occur when E. coli is straved for tryptophan ?a)The ribosome translates the leader peptide completelyb)Transcription reads through attenuator into trp EDCBAc)Tryptophanyl tRNA is not formedd)A stem loop structure involving regions 3 and 4 is formed at attenuator site.Correct answer is option 'B,C'. Can you explain this answer?.
Solutions for Which of the following events occur when E. coli is straved for tryptophan ?a)The ribosome translates the leader peptide completelyb)Transcription reads through attenuator into trp EDCBAc)Tryptophanyl tRNA is not formedd)A stem loop structure involving regions 3 and 4 is formed at attenuator site.Correct answer is option 'B,C'. Can you explain this answer? in English & in Hindi are available as part of our courses for IIT JAM. Download more important topics, notes, lectures and mock test series for IIT JAM Exam by signing up for free.
Here you can find the meaning of Which of the following events occur when E. coli is straved for tryptophan ?a)The ribosome translates the leader peptide completelyb)Transcription reads through attenuator into trp EDCBAc)Tryptophanyl tRNA is not formedd)A stem loop structure involving regions 3 and 4 is formed at attenuator site.Correct answer is option 'B,C'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of Which of the following events occur when E. coli is straved for tryptophan ?a)The ribosome translates the leader peptide completelyb)Transcription reads through attenuator into trp EDCBAc)Tryptophanyl tRNA is not formedd)A stem loop structure involving regions 3 and 4 is formed at attenuator site.Correct answer is option 'B,C'. Can you explain this answer?, a detailed solution for Which of the following events occur when E. coli is straved for tryptophan ?a)The ribosome translates the leader peptide completelyb)Transcription reads through attenuator into trp EDCBAc)Tryptophanyl tRNA is not formedd)A stem loop structure involving regions 3 and 4 is formed at attenuator site.Correct answer is option 'B,C'. Can you explain this answer? has been provided alongside types of Which of the following events occur when E. coli is straved for tryptophan ?a)The ribosome translates the leader peptide completelyb)Transcription reads through attenuator into trp EDCBAc)Tryptophanyl tRNA is not formedd)A stem loop structure involving regions 3 and 4 is formed at attenuator site.Correct answer is option 'B,C'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice Which of the following events occur when E. coli is straved for tryptophan ?a)The ribosome translates the leader peptide completelyb)Transcription reads through attenuator into trp EDCBAc)Tryptophanyl tRNA is not formedd)A stem loop structure involving regions 3 and 4 is formed at attenuator site.Correct answer is option 'B,C'. Can you explain this answer? tests, examples and also practice IIT JAM tests.
Explore Courses for IIT JAM exam

Suggested Free Tests

Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev