ANIMAL PHYSIOLOGY
CHEMICAL SIGNALS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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They regulate the synthesis of DNA in response to a signal.
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They transcribe ATP into cAMP.
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They initiate the epinephrine response in animal cells.
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They control gene expression.
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Detailed explanation-1: -And so the correct answer is that they control which genes are turned on to form MRNA transcription factors are proteins that regulate the transcription of genes.
Detailed explanation-2: -Transcription factors are proteins that help turn specific genes “on” or “off” by binding to nearby DNA. Transcription factors that are activators boost a gene’s transcription. Repressors decrease transcription.
Detailed explanation-3: -The activity of a transcription factor is often regulated by (de) phosphorylation, which may affect different functions, e.g. nuclear localization DNA binding and trans-activation. Ligand binding is another mode of transcription-factor activation. It is typical for the large super-family of nuclear hormone receptors.
Detailed explanation-4: -Gene expression is primarily controlled at the level of transcription, largely as a result of binding of proteins to specific sites on DNA.