In regulation by repressiona. a sugar, such as lactose, acts as an inducer and combines with the repressor to prevent transcription. b. an amino acid activates the repressor so that the repressor binds to the operator and prevents transcription. c. an inducer activates the activator so that it binds to DNA and prevents transcription. d. an amino acid binds to the operator, blocking the repressor, allowing transcription to proceed.

In regulation by repression "an amino acid activates the repressor so that the repressor binds to the operator and prevents transcription".

Option: B

Explanation:

A repressor refers RNA- or DNA inbuilt protein which impedes more than one gene transcription when inbuilt to an operator or related silencer in molecular genetics. A DNA-binding repressor restricts the RNA polymerase linkage to the promoter, stopping the genes from staying transcribed into messenger(mRNA).

An RNA-binding repressor binds to mRNA and prevents the mRNA from being converted into protein. This blockage of speech is known as repression. In this, a protein entity called a repressor inhibits the production of an enzyme by binding and thus blocking the function of deoxyribonucleic acid, which regulates the mechanism by which the enzyme is synthesized.

It is to apply genomic knowledge effectively in

drug discovery, mechanistic connectivities

between genetic variation and disease

processes need to be established via

systems biology approaches. Humans have

hundreds of functionally specialized cell

types that interact differentially with

environmental factors to influence disease

development and to modulate the effects of

drugs. Metabonomics can provide a means

of modelling these interactions, but the

relationships between ‘endogenous’

metabolic processes and

‘xenobiotic’ metabolism

are poorly understood, especially with

respect to environmental factors. We

present an overview of ‘global’ mammalian

metabolic conversions that should be

accounted for in human systems biology

models and propose a new probabilistic. Approach to help understand gene–disease relationships and vexed

issues of idiosyncratic drug toxicit etc.

Thus this is the required answer.  

Explanation: