In multiple sclerosis, the myelin sheaths around the axons of the brain and spinal cord are damaged and demyelination results. How does this disease manifest at the level of the action potential?

 I) Action potentials move in the opposite direction on the axon.

 II) Action potentials move more slowly along the axon.

 III) No action potentials are transmitted.

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#Question id: 4340

#Part-A Aptitude & General Biotechnology

There is a mutation that is found in E. coli in the repressor that results in a molecule known as a super-repressor because it represses the lac operon permanently. Which of the following characteristics would you expect to observe in such a mutant?

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#Question id: 4344

#Part-A Aptitude & General Biotechnology

How does the transcription of structural genes in an inducible operon occur?

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#Question id: 4345

#Part-A Aptitude & General Biotechnology

For a repressible operon to be transcribed, which of the following conditions must occur?

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#Question id: 4346

#Part-A Aptitude & General Biotechnology

Which of the following results would occur if the repressor of an inducible operon were mutated so that it could not bind the operator?

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#Question id: 4347

#Part-A Aptitude & General Biotechnology

According to the lac operon model proposed by Jacob and Monod, what is predicted to occur if the operator is removed from the operon?

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#Question id: 4348

#Part-A Aptitude & General Biotechnology

Under what conditions does the trp repressor block transcription of the trp operon?