Which of the Following Is True Regarding the Regulation of the Trp

question 43

Multiple Choice

Which of the following is true regarding the regulation of the trp operon?

• A) trpR mutants that lack functional repressor have a tenfold elevated rate of synthesis of the tryptophan biosynthetic enzymes in the presence of tryptophan.
• B) Tryptophan is an inducer of the trp operon.
• C) trpL deletion mutants in which there is no 162-nucleotide-long leader sequence in the mRNA result in relief of repression and derepression of the trp operon.
• D) Premature termination of the trp operon occurs in the presence of tryptophan charged tRNAt?p.
• E) In the presence of tryptophan, the ribosome cannot translate past the Trp codons to the leader-peptide termination codon.

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Definitions:

Withholding Reinforcement

is a behavioral strategy where a positive outcome or reward is not given, aiming to decrease or eliminate a certain behavior.

Extinction

In behavior psychology, the gradual disappearance of a conditioned response when the conditioned stimulus is no longer paired with the unconditioned stimulus.

Operant Conditioning

The technique of adjusting the intensity of an action by applying encouragements or deterrents.

Voluntary Behavior

Actions undertaken by an individual that are done by choice, without external compulsion.